Libslirp
CVE-2020-1983
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Memory lifecycle management
MITRE ATT&CK
2 techniques across 2 tactics: Execution, Privilege Escalation The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.5 (MEDIUM). Attack characteristics: local attack vector, low complexity, low privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | A local attacker with access to the system could access freed memory to execute arbitrary code or crash the application. |
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Alert meAnalysisAI
A use after free vulnerability in ip_reass() in ip_input.c of libslirp 4.2.0 and prior releases allows crafted packets to cause a denial of service. Rated medium severity (CVSS 6.5), this vulnerability is low attack complexity. Public exploit code available.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Use smart pointers or garbage-collected languages. Set pointers to NULL after freeing. Enable memory sanitizers.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Use After Free (CWE-416), which allows attackers to access freed memory to execute arbitrary code or crash the application. A use after free vulnerability in ip_reass() in ip_input.c of libslirp 4.2.0 and prior releases allows crafted packets to cause a denial of service. Affected products include: Libslirp Project Libslirp, Fedoraproject Fedora, Debian Debian Linux, Opensuse Leap, Canonical Ubuntu Linux.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
A use after free vulnerability in ip_reass() in ip_input.c of libslirp 4.2.0 and prior releases allows crafted packets to cause a denial of service.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Use-after-free vulnerabilities occur when a program continues to access memory through a pointer after that memory has been deallocated.
Memory corruption occurs when a program writes data beyond the boundaries of allocated memory regions or accesses memory in unintended ways, violating the integrity of the process's address space.
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)NVD
ip_reass in ip_input.c in libslirp 4.0.0 has a heap-based buffer overflow via a large packet because it mishandles a cas
slirp.c in libslirp through 4.3.1 has a buffer over-read because it tries to read a certain amount of header data even i
tftp.c in libslirp 4.1.0, as used in QEMU 4.2.0, does not prevent ..\ directory traversal on Windows. Rated high severit
libslirp 4.0.0, as used in QEMU 4.1.0, has a use-after-free in ip_reass in ip_input.c. Rated high severity (CVSS 7.5), t
Out-of-bounds heap read and integer underflow in libslirp's TCP urgent data handler (sosendoob) exposes gigabytes of hos
An out-of-bounds read vulnerability was found in the SLiRP networking implementation of the QEMU emulator. Rated medium
In libslirp 4.1.0, as used in QEMU 4.2.0, tcp_subr.c misuses snprintf return values, leading to a buffer overflow in lat
tcp_emu in tcp_subr.c in libslirp 4.1.0, as used in QEMU 4.2.0, mismanages memory, as demonstrated by IRC DCC commands i
ncsi.c in libslirp through 4.3.1 has a buffer over-read because it tries to read a certain amount of header data even if
An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. Rated low severity (CV
An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. Rated low severity (CV
An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. Rated low severity (CV
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB