7 Zip
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Heap-based buffer overflow in 7-Zip's XZ archive parser enables arbitrary code execution when a victim opens a crafted archive on 7-Zip 26.01 and earlier; fixed in 7-Zip 26.02. Reported by Landon Peng of Lunbun LLC through the Zero Day Initiative, this flaw carries full confidentiality, integrity, and availability impact at the process level. A public POC is confirmed available via the Italian ACN portal, though EPSS sits at only 0.92% (57th percentile) and no CISA KEV listing exists, indicating targeted rather than widespread exploitation at time of analysis.
Remote code execution in 7-Zip versions 26.00 and earlier is achievable via a crafted NTFS image that triggers a heap buffer overflow in the archive handler, overwriting an adjacent C++ object's vtable pointer to hijack control flow. The flaw stems from an undefined-behavior shift in CInStream::GetCuSize() that under-allocates a buffer to just one byte, which is then written up to 256 MB of attacker-controlled data. Exploitation requires the victim to open or extract a malicious archive (UI:R), but the NTFS handler is enabled by default and is selected via signature matching regardless of file extension; no public exploit identified at time of analysis.
7-Zip contains a Mark-of-the-Web bypass vulnerability allowing attackers to circumvent Windows security warnings when extracting files from malicious archives, exploited in campaigns targeting Ukrainian organizations.
Mark-of-the-Web protection is bypassed in 7-Zip for Windows 26.02 and earlier when extracting crafted RAR5 archives, allowing an attacker to strip the Internet-zone marker (ZoneId=0) and spoof the extracted file's data stream content - directly defeating SmartScreen and Windows attachment warnings. The bypass exploits a gap between 7-Zip's exact-string guard ('Zone.Identifier') and the NTFS-canonical equivalent (':Zone.Identifier:$DATA') that a RAR5 STM record can supply; a second STM record ('::$DATA') additionally overwrites the default file data stream for content spoofing. A publicly available proof-of-concept exists; no vendor-released patched version has been confirmed at the time of analysis.
Heap out-of-bounds read in 7-Zip's Unix ar archive parser (versions 9.18 through 26.00) allows a remote unauthenticated attacker to leak uninitialized heap memory contents by convincing a user to open a specially crafted archive. The ParseLibSymbols function mishandles the BSD-style __.SYMDEF symbol table by reading 4 bytes past the end of a heap allocation when the namesSize field position equals the buffer boundary, exposing heap data with high confidentiality impact. No public exploit has been identified at time of analysis, and no KEV listing exists; version 26.01 patches the issue.
Off-by-one out-of-bounds read in 7-Zip's UEFI firmware image parser (versions 9.21-26.00) allows a network-adjacent attacker to trigger either a denial of service (application crash) or minor information disclosure of an adjacent static .rdata string literal into archive metadata, simply by convincing a user to open a crafted UEFI-containing archive. The vulnerability is reached automatically upon archive open with no special user action beyond opening the file, and affects default 7-Zip installations because the UEFI handler is enabled out-of-the-box. No public exploit code has been identified at time of analysis, no KEV listing exists, and the impact is bounded: there is no write primitive and no disclosure of heap data, secrets, or ASLR base addresses.
Uninitialized heap read in 7-Zip's SquashFS archive handler (versions 9.18 through 26.00) can crash the application and leak raw heap memory contents when a user opens a specially crafted archive. The flaw originates in the `_blockToNode` array, which is allocated but never zero-initialized; an attacker-controlled `blockIndex` derived from the RootInode superblock field drives a binary search over uninitialized slots, producing a chained out-of-bounds read with no write primitive. No public exploit has been identified at time of analysis, and the description explicitly characterizes exploitation as heap-layout-dependent and not reliably triggerable, which is consistent with the CVSS AC:H rating and limits practical risk despite the network-deliverable attack surface.
Off-by-one heap out-of-bounds read in 7-Zip's WIM archive handler (versions 9.34-26.00) allows a remote unauthenticated attacker to trigger denial of service - and potentially minor information disclosure - by delivering a crafted WIM file. The vulnerability is zero-click exploitable in the GUI: 7zFM.exe automatically calls GetRawProp(kpidNtSecure) for every listed item, triggering the OOB read without any additional user interaction beyond opening or navigating to the malicious archive. No public exploit code has been identified at time of analysis, and the vulnerability is not listed in the CISA KEV catalog.
Heap out-of-bounds read in 7-Zip versions 9.11 through 26.00 exposes up to 3 bytes of heap memory during UDF disc image parsing, triggering when a user opens or extracts a crafted .iso or .udf file. Impact is constrained to a 1-bit information-disclosure oracle per out-of-bounds byte (inferred from open/fail behavior) and potential denial of service under hardened allocators; no write primitive exists. No public exploit code or CISA KEV listing has been identified at time of analysis, and the CVSS Low score of 3.1 accurately reflects the limited real-world severity.
Uninitialized heap memory disclosure in 7-Zip's UEFI capsule (.scap) parser exposes potentially sensitive heap contents when an unauthenticated remote attacker delivers a crafted capsule file that a user opens. The OpenCapsule function allocates a heap buffer sized by the attacker-controlled CapsuleImageSize field without zero-initialization, then silently ignores read failures on truncated files, causing the unread tail - containing raw heap data - to be surfaced as extracted file content. Affecting versions 9.21 through 26.00, a fix is available in 26.0.1; no public exploit code has been identified at time of analysis.
Heap memory disclosure in 7-Zip 9.34 through 26.00 (32-bit builds only) allows a remote unauthenticated attacker to leak arbitrary heap contents into attacker-controlled extracted files by supplying a crafted SquashFS archive. The root cause is a 32-bit integer overflow in the SquashFS ReadBlock function: because size_t is 32 bits on 32-bit builds, the addition of offsetInBlock and blockSize wraps modulo 2³², bypassing the fragment bounds check and directing memcpy to read heap memory preceding the intended cache buffer. No public exploit has been identified at time of analysis, and no CISA KEV listing exists. Version 26.01 patches the issue.
7-Zip ZIP File Parsing Directory Traversal Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of 7-Zip. [CVSS 7.8 HIGH]
7-Zip ZIP File Parsing Directory Traversal Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
7-Zip before 25.01 does not always properly handle symbolic links during extraction. Rated low severity (CVSS 3.6), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Heap buffer overflow in 7-Zip's RAR5 handler writes zeroes beyond allocated heap memory, causing memory corruption and denial of service in versions prior to 25.0.0. Local attackers can trigger this vulnerability by crafting malicious RAR5 archive files. Publicly available exploit code exists, making this a moderate-priority local vulnerability despite its network-isolated attack surface.
7-Zip 22.01 does not report an error for certain invalid xz files, involving stream flags and reserved bits. Rated low severity (CVSS 2.5), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
7-Zip 22.01 does not report an error for certain invalid xz files, involving block flags and reserved bits. Rated low severity (CVSS 2.5), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
7-Zip CopyCoder Infinite Loop Denial-of-Service Vulnerability. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Ppmd7.c in 7-Zip before 23.00 allows an integer underflow and invalid read operation via a crafted 7Z archive. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
7-Zip through 21.07 on Windows allows privilege escalation and command execution when a file with the .7z extension is dragged to the Help>Contents area. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available and no vendor patch available.
Incorrect initialization logic of RAR decoder objects in 7-Zip 18.03 and before can lead to usage of uninitialized memory, allowing remote attackers to cause a denial of service (segmentation fault). Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
7-Zip through 18.01 on Windows implements the "Large memory pages" option by calling the LsaAddAccountRights function to add the SeLockMemoryPrivilege privilege to the user's account, which makes it. Rated high severity (CVSS 8.8), this vulnerability is low attack complexity. No vendor patch available.
Insufficient exception handling in the method NCompress::NRar3::CDecoder::Code of 7-Zip before 18.00 and p7zip can lead to multiple memory corruptions within the PPMd code, allows remote attackers to. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Untrusted search path vulnerability in 7 Zip for Windows 16.02 and earlier allows remote attackers to gain privileges via a Trojan horse DLL in an unspecified directory. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Heap-based buffer overflow in the NArchive::NHfs::CHandler::ExtractZlibFile method in 7zip before 16.00 and p7zip allows remote attackers to execute arbitrary code via a crafted HFS+ image. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and EPSS exploitation probability 16.3%.
A null pointer dereference bug affects the 16.02 and many old versions of p7zip. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
The CInArchive::ReadFileItem method in Archive/Udf/UdfIn.cpp in 7zip 9.20 and 15.05 beta and p7zip allows remote attackers to cause a denial of service (out-of-bounds read) or execute arbitrary code. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
p7zip 9.20.1 allows remote attackers to write to arbitrary files via a symlink attack in an archive. Rated medium severity (CVSS 5.8), this vulnerability is remotely exploitable. Public exploit code available and no vendor patch available.
Heap-based buffer overflow in 7-Zip's XZ archive parser enables arbitrary code execution when a victim opens a crafted archive on 7-Zip 26.01 and earlier; fixed in 7-Zip 26.02. Reported by Landon Peng of Lunbun LLC through the Zero Day Initiative, this flaw carries full confidentiality, integrity, and availability impact at the process level. A public POC is confirmed available via the Italian ACN portal, though EPSS sits at only 0.92% (57th percentile) and no CISA KEV listing exists, indicating targeted rather than widespread exploitation at time of analysis.
Remote code execution in 7-Zip versions 26.00 and earlier is achievable via a crafted NTFS image that triggers a heap buffer overflow in the archive handler, overwriting an adjacent C++ object's vtable pointer to hijack control flow. The flaw stems from an undefined-behavior shift in CInStream::GetCuSize() that under-allocates a buffer to just one byte, which is then written up to 256 MB of attacker-controlled data. Exploitation requires the victim to open or extract a malicious archive (UI:R), but the NTFS handler is enabled by default and is selected via signature matching regardless of file extension; no public exploit identified at time of analysis.
7-Zip contains a Mark-of-the-Web bypass vulnerability allowing attackers to circumvent Windows security warnings when extracting files from malicious archives, exploited in campaigns targeting Ukrainian organizations.
Mark-of-the-Web protection is bypassed in 7-Zip for Windows 26.02 and earlier when extracting crafted RAR5 archives, allowing an attacker to strip the Internet-zone marker (ZoneId=0) and spoof the extracted file's data stream content - directly defeating SmartScreen and Windows attachment warnings. The bypass exploits a gap between 7-Zip's exact-string guard ('Zone.Identifier') and the NTFS-canonical equivalent (':Zone.Identifier:$DATA') that a RAR5 STM record can supply; a second STM record ('::$DATA') additionally overwrites the default file data stream for content spoofing. A publicly available proof-of-concept exists; no vendor-released patched version has been confirmed at the time of analysis.
Heap out-of-bounds read in 7-Zip's Unix ar archive parser (versions 9.18 through 26.00) allows a remote unauthenticated attacker to leak uninitialized heap memory contents by convincing a user to open a specially crafted archive. The ParseLibSymbols function mishandles the BSD-style __.SYMDEF symbol table by reading 4 bytes past the end of a heap allocation when the namesSize field position equals the buffer boundary, exposing heap data with high confidentiality impact. No public exploit has been identified at time of analysis, and no KEV listing exists; version 26.01 patches the issue.
Off-by-one out-of-bounds read in 7-Zip's UEFI firmware image parser (versions 9.21-26.00) allows a network-adjacent attacker to trigger either a denial of service (application crash) or minor information disclosure of an adjacent static .rdata string literal into archive metadata, simply by convincing a user to open a crafted UEFI-containing archive. The vulnerability is reached automatically upon archive open with no special user action beyond opening the file, and affects default 7-Zip installations because the UEFI handler is enabled out-of-the-box. No public exploit code has been identified at time of analysis, no KEV listing exists, and the impact is bounded: there is no write primitive and no disclosure of heap data, secrets, or ASLR base addresses.
Uninitialized heap read in 7-Zip's SquashFS archive handler (versions 9.18 through 26.00) can crash the application and leak raw heap memory contents when a user opens a specially crafted archive. The flaw originates in the `_blockToNode` array, which is allocated but never zero-initialized; an attacker-controlled `blockIndex` derived from the RootInode superblock field drives a binary search over uninitialized slots, producing a chained out-of-bounds read with no write primitive. No public exploit has been identified at time of analysis, and the description explicitly characterizes exploitation as heap-layout-dependent and not reliably triggerable, which is consistent with the CVSS AC:H rating and limits practical risk despite the network-deliverable attack surface.
Off-by-one heap out-of-bounds read in 7-Zip's WIM archive handler (versions 9.34-26.00) allows a remote unauthenticated attacker to trigger denial of service - and potentially minor information disclosure - by delivering a crafted WIM file. The vulnerability is zero-click exploitable in the GUI: 7zFM.exe automatically calls GetRawProp(kpidNtSecure) for every listed item, triggering the OOB read without any additional user interaction beyond opening or navigating to the malicious archive. No public exploit code has been identified at time of analysis, and the vulnerability is not listed in the CISA KEV catalog.
Heap out-of-bounds read in 7-Zip versions 9.11 through 26.00 exposes up to 3 bytes of heap memory during UDF disc image parsing, triggering when a user opens or extracts a crafted .iso or .udf file. Impact is constrained to a 1-bit information-disclosure oracle per out-of-bounds byte (inferred from open/fail behavior) and potential denial of service under hardened allocators; no write primitive exists. No public exploit code or CISA KEV listing has been identified at time of analysis, and the CVSS Low score of 3.1 accurately reflects the limited real-world severity.
Uninitialized heap memory disclosure in 7-Zip's UEFI capsule (.scap) parser exposes potentially sensitive heap contents when an unauthenticated remote attacker delivers a crafted capsule file that a user opens. The OpenCapsule function allocates a heap buffer sized by the attacker-controlled CapsuleImageSize field without zero-initialization, then silently ignores read failures on truncated files, causing the unread tail - containing raw heap data - to be surfaced as extracted file content. Affecting versions 9.21 through 26.00, a fix is available in 26.0.1; no public exploit code has been identified at time of analysis.
Heap memory disclosure in 7-Zip 9.34 through 26.00 (32-bit builds only) allows a remote unauthenticated attacker to leak arbitrary heap contents into attacker-controlled extracted files by supplying a crafted SquashFS archive. The root cause is a 32-bit integer overflow in the SquashFS ReadBlock function: because size_t is 32 bits on 32-bit builds, the addition of offsetInBlock and blockSize wraps modulo 2³², bypassing the fragment bounds check and directing memcpy to read heap memory preceding the intended cache buffer. No public exploit has been identified at time of analysis, and no CISA KEV listing exists. Version 26.01 patches the issue.
7-Zip ZIP File Parsing Directory Traversal Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of 7-Zip. [CVSS 7.8 HIGH]
7-Zip ZIP File Parsing Directory Traversal Remote Code Execution Vulnerability. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
7-Zip before 25.01 does not always properly handle symbolic links during extraction. Rated low severity (CVSS 3.6), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Heap buffer overflow in 7-Zip's RAR5 handler writes zeroes beyond allocated heap memory, causing memory corruption and denial of service in versions prior to 25.0.0. Local attackers can trigger this vulnerability by crafting malicious RAR5 archive files. Publicly available exploit code exists, making this a moderate-priority local vulnerability despite its network-isolated attack surface.
7-Zip 22.01 does not report an error for certain invalid xz files, involving stream flags and reserved bits. Rated low severity (CVSS 2.5), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
7-Zip 22.01 does not report an error for certain invalid xz files, involving block flags and reserved bits. Rated low severity (CVSS 2.5), this vulnerability is no authentication required. Public exploit code available and no vendor patch available.
7-Zip CopyCoder Infinite Loop Denial-of-Service Vulnerability. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Ppmd7.c in 7-Zip before 23.00 allows an integer underflow and invalid read operation via a crafted 7Z archive. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
7-Zip through 21.07 on Windows allows privilege escalation and command execution when a file with the .7z extension is dragged to the Help>Contents area. Rated high severity (CVSS 7.8), this vulnerability is low attack complexity. Public exploit code available and no vendor patch available.
Incorrect initialization logic of RAR decoder objects in 7-Zip 18.03 and before can lead to usage of uninitialized memory, allowing remote attackers to cause a denial of service (segmentation fault). Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
7-Zip through 18.01 on Windows implements the "Large memory pages" option by calling the LsaAddAccountRights function to add the SeLockMemoryPrivilege privilege to the user's account, which makes it. Rated high severity (CVSS 8.8), this vulnerability is low attack complexity. No vendor patch available.
Insufficient exception handling in the method NCompress::NRar3::CDecoder::Code of 7-Zip before 18.00 and p7zip can lead to multiple memory corruptions within the PPMd code, allows remote attackers to. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Untrusted search path vulnerability in 7 Zip for Windows 16.02 and earlier allows remote attackers to gain privileges via a Trojan horse DLL in an unspecified directory. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Heap-based buffer overflow in the NArchive::NHfs::CHandler::ExtractZlibFile method in 7zip before 16.00 and p7zip allows remote attackers to execute arbitrary code via a crafted HFS+ image. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Public exploit code available and EPSS exploitation probability 16.3%.
A null pointer dereference bug affects the 16.02 and many old versions of p7zip. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
The CInArchive::ReadFileItem method in Archive/Udf/UdfIn.cpp in 7zip 9.20 and 15.05 beta and p7zip allows remote attackers to cause a denial of service (out-of-bounds read) or execute arbitrary code. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
p7zip 9.20.1 allows remote attackers to write to arbitrary files via a symlink attack in an archive. Rated medium severity (CVSS 5.8), this vulnerability is remotely exploitable. Public exploit code available and no vendor patch available.