Unrar
CVE-2017-14121
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A10:2025 - Mishandling of Exceptional Conditions
ASVS 5.0
V16 - Security Logging and Error Handling Null pointer safety, defensive checks
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 5.5 (MEDIUM). Attack characteristics: local attack vector, low complexity, no privileges required, user interaction required. EPSS exploitation probability: 0.19%. |
| Exploit ScenarioDerived | A local attacker with access to the system could crash the application by dereferencing a null pointer. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
The DecodeNumber function in unrarlib.c in unrar 0.0.1 (aka unrar-free or unrar-gpl) suffers from a NULL pointer dereference flaw triggered by a crafted RAR archive. Rated medium severity (CVSS 5.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Check pointers before dereferencing. Use static analysis tools to detect null pointer paths.
Affects your stack
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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 NULL Pointer Dereference (CWE-476), which allows attackers to crash the application by dereferencing a null pointer. The DecodeNumber function in unrarlib.c in unrar 0.0.1 (aka unrar-free or unrar-gpl) suffers from a NULL pointer dereference flaw triggered by a crafted RAR archive. NOTE: this may be the same as one of the several test cases in the CVE-2017-11189 references. Affected products include: Rarlab Unrar, Debian Debian 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:N/UI:R/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
The DecodeNumber function in unrarlib.c in unrar 0.0.1 (aka unrar-free or unrar-gpl) suffers from a NULL pointer dereference flaw triggered by a crafted RAR archive. NOTE: this may be the same as one of the several test cases in the CVE-2017-11189 references.
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
A null pointer dereference occurs when a program attempts to access memory through a pointer that has been set to NULL (address 0x0).
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)CVE.org
RARLAB UnRAR before 6.12 on Linux and UNIX allows directory traversal to write to files during an extract (aka unpack) o
A VMSF_DELTA memory corruption was discovered in unrar before 5.5.5, as used in Sophos Anti-Virus Threat Detection Engin
libunrar.a in UnRAR before 5.5.7 has an out-of-bounds read in the Unpack::Unpack20 function. Rated critical severity (CV
libunrar.a in UnRAR before 5.5.7 has a buffer overflow in the Unpack::LongLZ function. Rated critical severity (CVSS 9.8
libunrar.a in UnRAR before 5.5.7 has an out-of-bounds read in the EncodeFileName::Decode call within the Archive::ReadHe
UnRAR before 5.5.7 allows remote attackers to bypass a directory-traversal protection mechanism via vectors involving a
unrar 0.0.1 (aka unrar-free or unrar-gpl) suffers from a stack-based buffer over-read in unrarlib.c, related to ExtrFile
Out-of-bounds heap write in the RAR5 recovery-volume (.rev) parser of WinRAR, RAR, UnRAR, and unrar.dll (versions before
unrar 0.0.1 (aka unrar-free or unrar-gpl) suffers from a directory traversal vulnerability for RAR v2 archives: pathname
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB