Buffer Overflow
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
How It Works
A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions. This overwrites whatever data or code exists there, corrupting program state and potentially giving attackers control over execution flow.
Stack-based overflows are the most common variant. When a function allocates a fixed-size buffer on the stack and then copies user-controlled input without proper bounds checking, attackers can overflow past the buffer to overwrite the function's return address. When the function completes, instead of returning to legitimate code, execution jumps to attacker-specified memory containing malicious shellcode. Heap-based overflows work differently—they corrupt heap metadata like chunk size fields or free list pointers, leading to arbitrary memory writes when the allocator processes the corrupted structures.
Modern exploitation bypasses defensive mechanisms through techniques like Return-Oriented Programming (ROP), which chains together existing code snippets to avoid non-executable memory protections. Attackers may also use heap spraying to reliably position shellcode at predictable addresses, defeating address randomization.
Impact
- Remote code execution — attacker gains ability to run arbitrary commands with the privileges of the vulnerable process
- Privilege escalation — exploiting kernel or setuid program overflows to gain root/SYSTEM access
- Denial of service — crashes and memory corruption that render systems unusable
- Information disclosure — reading sensitive data from adjacent memory regions that should be inaccessible
- Authentication bypass — overwriting security-critical variables like permission flags or user IDs
Real-World Examples
Fortinet FortiOS suffered a critical buffer overflow (CVE-2025-32756) that allowed unauthenticated remote attackers to execute code as root on firewalls and VPN gateways. Attackers actively exploited this to compromise enterprise network perimeters before patches were available.
The Slammer worm from 2003 exploited a stack overflow in Microsoft SQL Server, spreading to 75,000 hosts in ten minutes by sending a single malformed UDP packet that overwrote the return address with shellcode. No authentication was required.
OpenSSH historically contained a heap overflow in challenge-response authentication that allowed pre-authentication remote root compromise on Unix systems, demonstrating how memory corruption in privileged network services creates maximum impact scenarios.
Mitigation
- Memory-safe languages — Rust, Go, and modern managed languages prevent buffer overflows by design through automatic bounds checking
- Stack canaries — random values placed before return addresses that detect corruption before control transfer
- Address Space Layout Randomization (ASLR) — randomizes memory locations making exploitation less reliable
- Data Execution Prevention (DEP/NX) — marks memory regions as non-executable, preventing direct shellcode execution
- Bounds checking — validate input sizes before copying, use safe functions like
strncpyinstead ofstrcpy - Fuzzing and static analysis — automated testing to discover overflows before deployment
Recent CVEs (36511)
In the Linux kernel, the following vulnerability has been resolved: bnxt_re: avoid shift undefined behavior in bnxt_qplib_alloc_init_hwq Undefined behavior is triggered when bnxt_qplib_alloc_init_hwq. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity.
In the Linux kernel, the following vulnerability has been resolved: net: sched: sch_multiq: fix possible OOB write in multiq_tune() q->bands will be assigned to qopt->bands to execute subsequent code. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. This Out-of-bounds Write vulnerability could allow attackers to write data beyond allocated buffer boundaries leading to code execution or crashes.
Actiontec WCB6200Q uh_get_postdata_withupload Stack-based Buffer Overflow Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Actiontec WCB6200Q Multipart Boundary Stack-based Buffer Overflow Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Actiontec WCB6200Q uh_tcp_recv_header Buffer Overflow Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Actiontec WCB6200Q uh_tcp_recv_content Buffer Overflow Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
vCenter Server contains a heap-overflow vulnerability in the implementation of the DCERPC protocol. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Out-of-bounds Write vulnerability could allow attackers to write data beyond allocated buffer boundaries leading to code execution or crashes.
vCenter Server contains a heap-overflow vulnerability in the implementation of the DCERPC protocol. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Out-of-bounds Write vulnerability could allow attackers to write data beyond allocated buffer boundaries leading to code execution or crashes.
oqs-provider is a provider for the OpenSSL 3 cryptography library that adds support for post-quantum cryptography in TLS, X.509, and S/MIME using post-quantum algorithms from liboqs. Rated high severity (CVSS 8.2), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A segmentation fault in CVC5 Solver v1.1.3 allows attackers to cause a Denial of Service (DoS) via a crafted SMT-LIB input file containing the `set-logic` command with specific formatting errors. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
C/sorting/binary_insertion_sort.c in The Algorithms - C through e5dad3f has a segmentation fault for deep recursion, which may affect common use cases such as sorting an array of 50 elements. Rated medium severity (CVSS 6.2), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
TRENDnet TEW-814DAP v1_(FW1.01B01) was discovered to contain a stack overflow vulnerability via the submit-url parameter at /formSysLog . Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
TRENDnet TEW-814DAP v1_(FW1.01B01) was discovered to contain a stack overflow vulnerability via the submit-url parameter at /formPasswordAuth . Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
TRENDnet TEW-814DAP v1_(FW1.01B01) was discovered to contain a stack overflow via the submit-url parameter at /formNewSchedule. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via ssid5g in the function setWiFiEasyGuestCfg. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via eport in the function setIpPortFilterRules. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via ssid5g in the function setWizardCfg. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Out-of-bounds read vulnerability in the audio module Impact: Successful exploitation of this vulnerability will affect availability. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
Memory management vulnerability in the boottime module Impact: Successful exploitation of this vulnerability can affect integrity. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
ASUS Download Master has a buffer overflow vulnerability. Rated high severity (CVSS 7.2), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Certain models of ASUS routers have buffer overflow vulnerabilities, allowing remote attackers with administrative privileges to execute arbitrary commands on the device. Rated high severity (CVSS 7.2), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
NVIDIA vGPU software for Linux contains a vulnerability in the Virtual GPU Manager, where the guest OS could cause buffer overrun in the host. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
NVIDIA GPU driver for Windows and Linux contains a vulnerability where a user can cause an out-of-bounds write. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In dhd_prot_txstatus_process of dhd_msgbuf.c, there is a possible out of bounds write due to a missing bounds check. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In lwis_initialize_transaction_fences of lwis_fence.c, there is a possible out of bounds write due to a missing bounds check. Rated high severity (CVSS 7.4), this vulnerability is no authentication required. No vendor patch available.
In set_secure_reg of sac_handler.c, there is a possible out of bounds read due to a missing bounds check. Rated high severity (CVSS 7.1), this vulnerability is low attack complexity. No vendor patch available.
In pl330_dma_from_peri_start() of fp_spi_dma.c, there is a possible out of bounds write due to a missing bounds check. Rated high severity (CVSS 7.1), this vulnerability is low attack complexity. No vendor patch available.
In CellInfoListParserV2::FillCellInfo() of protocolnetadapter.cpp, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
In tpu_get_int_state of tpu.c, there is a possible information disclosure due to uninitialized data. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
In wl_notify_rx_mgmt_frame of wl_cfg80211.c, there is a possible out of bounds write due to an integer overflow. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In handle_msg of main.cpp, there is a possible out of bounds write due to a heap buffer overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In memcall_add of memlog.c, there is a possible buffer overflow due to improper input validation. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In circ_read of link_device_memory_legacy.c, there is a possible out of bounds write due to an incorrect bounds check. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In ProtocolVsimOperationAdapter() of protocolvsimadapter.cpp, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.7). No vendor patch available.
In prepare_response_locked of lwis_transaction.c, there is a possible out of bounds write due to improper input validation. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In v4l2_smfc_qbuf of smfc-v4l2-ioctls.c, there is a possible out of bounds write due to a missing bounds check. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In ProtocolCellIdentityParserV4::Parse() of protocolnetadapter.cpp, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.7). No vendor patch available.
In ProtocolCdmaCallWaitingIndAdapter::GetCwInfo() of protocolsmsadapter.cpp, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 5.9), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
In BCMFASTPATH of dhd_msgbuf.c, there is a possible out of bounds write due to a missing bounds check. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In bc_get_converted_received_bearer of bc_utilities.c, there is a possible out of bounds read due to a missing bounds check. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In _s5e9865_mif_set_rate of exynos_dvfs.c, there is a possible out of bounds read due to improper casting. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
In handle_init of goodix/main/main.c, there is a possible memory corruption due to type confusion. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In sec_media_unprotect of media.c, there is a possible memory corruption due to a race condition. Rated high severity (CVSS 7.0). No vendor patch available.
In pktproc_fill_data_addr_without_bm of link_rx_pktproc.c, there is a possible out of bounds write due to a missing bounds check. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In prepare_response of lwis_periodic_io.c, there is a possible out of bounds write due to an integer overflow. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
In ss_AnalyzeOssReturnResUssdArgIe of ss_OssAsnManagement.c, there is a possible out of bounds read due to improper input validation. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In ProtocolPsDedicatedBearInfoAdapter::processQosSession of protocolpsadapter.cpp, there is a possible out of bounds read due to a missing bounds check. Rated medium severity (CVSS 4.7). No vendor patch available.
Deep Sea Electronics DSE855 Multipart Value Handling Stack-Based Buffer Overflow Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Deep Sea Electronics DSE855 Multipart Boundary Stack-Based Buffer Overflow Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via ssid in the function setWiFiBasicCfg. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via ssid in the function setWiFiEasyCfg. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via ssid in the function setWiFiGuestCfg. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via the password parameter in function loginAuth . Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
TOTOLINK A3700R V9.1.2u.6165_20211012 was discovered to contain a stack overflow via the File parameter in function UploadCustomModule. Rated high severity (CVSS 8.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Fuji Electric Tellus Lite V-Simulator is vulnerable to a stack-based buffer overflow, which could allow an attacker to execute arbitrary code. Rated high severity (CVSS 8.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Fuji Electric Tellus Lite V-Simulator is vulnerable to an out-of-bounds write, which could allow an attacker to manipulate memory, resulting in execution of arbitrary code. Rated high severity (CVSS 8.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
A stack overflow vulnerability was found in version 1.18.0 of rhai. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A flaw was discovered in Elasticsearch, affecting document ingestion when an index template contains a dynamic field mapping of “passthrough” type. Rated medium severity (CVSS 4.9), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
An issue was discovered in Samsung Mobile Processor and Wearable Processor Exynos 850, Exynos 1080, Exynos 2100, Exynos 1280, Exynos 1380, Exynos 1330, Exynos W920, Exynos W930. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
An issue was discovered in Samsung Mobile Processor Exynos 2200, Exynos 1480, Exynos 2400. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
UERANSIM before 3.2.6 allows out-of-bounds read when a RLS packet is sent to gNodeB with malformed PDU length. Rated medium severity (CVSS 5.5), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Substance3D - Stager versions 2.1.4 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Photoshop Desktop versions 24.7.3, 25.7 and earlier are affected by an out-of-bounds read vulnerability when parsing a crafted file, which could result in a read past the end of an allocated memory. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Media Encoder versions 23.6.5, 24.3 and earlier Answer: are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Audition versions 24.2, 23.6.4 and earlier Answer: are affected by an out-of-bounds read vulnerability that could lead to disclosure of sensitive memory. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
device’s web interface when an attacker sends a specially crafted HTTP request. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
exists that could allow a user with access to the device’s web interface to cause a fault on the device when sending a malformed HTTP request. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, low attack complexity. This Buffer Copy without Size Check vulnerability could allow attackers to overflow a buffer to corrupt adjacent memory.
when sending a malformed POST request and particular configuration parameters are set. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
naga v0.14.0 was discovered to contain a stack overflow via the component /wgsl/parse/mod.rs. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Dell Client BIOS contains an Out-of-bounds Write vulnerability. Rated medium severity (CVSS 4.4), this vulnerability is low attack complexity. No vendor patch available.
Heap buffer overflow in Tab Strip in Google Chrome prior to 126.0.6478.54 allowed a remote attacker to perform an out of bounds memory read via a crafted HTML page. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Heap buffer overflow in Tab Groups in Google Chrome prior to 126.0.6478.54 allowed a remote attacker who convinced a user to engage in specific UI gestures to potentially exploit heap corruption via. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
MicroDicom DICOM Viewer is vulnerable to a stack-based buffer overflow, which may allow an attacker to execute arbitrary code on affected installations of DICOM Viewer. Rated high severity (CVSS 8.7), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
libiec61850 v1.5 was discovered to contain a heap overflow via the BerEncoder_encodeLength function at /asn1/ber_encoder.c. Rated high severity (CVSS 7.4), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
Windows Routing and Remote Access Service (RRAS) Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Windows Routing and Remote Access Service (RRAS) Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity.
Win32k Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Cloud Files Mini Filter Driver Elevation of Privilege Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity.
Windows Standards-Based Storage Management Service Denial of Service Vulnerability. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Windows OLE Remote Code Execution Vulnerability. Rated high severity (CVSS 8.0), this vulnerability is remotely exploitable, low attack complexity.
Windows Link Layer Topology Discovery Protocol Remote Code Execution Vulnerability. Rated high severity (CVSS 8.0), this vulnerability is no authentication required, low attack complexity.
Windows Link Layer Topology Discovery Protocol Remote Code Execution Vulnerability. Rated high severity (CVSS 8.0), this vulnerability is no authentication required, low attack complexity.
Windows Remote Access Connection Manager Information Disclosure Vulnerability. Rated medium severity (CVSS 4.7).
Windows Kernel Elevation of Privilege Vulnerability. Rated high severity (CVSS 8.8), this vulnerability is low attack complexity. This Out-of-bounds Read vulnerability could allow attackers to read data from memory outside the intended buffer boundaries.
Winlogon Elevation of Privilege Vulnerability. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity.
TOTOLINK AC1200 Wireless Dual Band Gigabit Router firmware A3100R V4.1.2cu.5247_B20211129, in the cgi function `setNoticeCfg` of the file `/lib/cste_modules/system.so`, the length of the user input. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A stack-based buffer overflow in Fortinet FortiPAM version 1.2.0, 1.1.0 through 1.1.2, 1.0.0 through 1.0.3, FortiWeb, FortiAuthenticator, FortiSwitchManager version 7.2.0 through 7.2.3, 7.0.1 through. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
A stack-based buffer overflow in Fortinet FortiOS version 7.4.0 through 7.4.2, 7.2.0 through 7.2.6, 7.0.0 through 7.0.13, 6.4.0 through 6.4.14, 6.2.0 through 6.2.15, 6.0 all versions allows attacker. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. No vendor patch available.
A heap-based buffer overflow vulnerability exists in the FOXMAN-UN/UNEM that if exploited will generally lead to a denial of service but can be used to execute arbitrary code, which is usually. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Memory corruption in the networking stack could have led to a potentially exploitable crash. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.