Unrar
CVE-2017-12940
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Bounds checking, read limits
MITRE ATT&CK
1 technique across 1 tactic: Collection The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. EPSS exploitation probability: 0.45%. |
| Exploit ScenarioDerived | A remote attacker could read data from memory outside the intended buffer boundaries by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
libunrar.a in UnRAR before 5.5.7 has an out-of-bounds read in the EncodeFileName::Decode call within the Archive::ReadHeader15 function. 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.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate array indices and buffer lengths. Use memory-safe languages. Enable AddressSanitizer during testing.
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 Out-of-bounds Read (CWE-125), which allows attackers to read data from memory outside the intended buffer boundaries. libunrar.a in UnRAR before 5.5.7 has an out-of-bounds read in the EncodeFileName::Decode call within the Archive::ReadHeader15 function. Affected products include: Rarlab Unrar. Version information: before 5.5.7.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
libunrar.a in UnRAR before 5.5.7 has an out-of-bounds read in the EncodeFileName::Decode call within the Archive::ReadHeader15 function.
Threat Intelligence Overview
NVD
CVE.org
EPSS
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 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.
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
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
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
The DecodeNumber function in unrarlib.c in unrar 0.0.1 (aka unrar-free or unrar-gpl) suffers from a NULL pointer derefer
GitHub PoC
Exploit-DB