Bash
CVE-2016-9401
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 5.5 (MEDIUM). Attack characteristics: local attack vector, low complexity, low privileges required, no user interaction not required. EPSS exploitation probability: 0.06%. |
| 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
popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address. Rated medium severity (CVSS 5.5), this vulnerability is low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Use smart pointers or garbage-collected languages. Set pointers to NULL after freeing. Enable memory sanitizers.
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 Use After Free (CWE-416), which allows attackers to access freed memory to execute arbitrary code or crash the application. popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address. Affected products include: Gnu Bash, Debian Debian Linux, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus.
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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:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address.
Threat Intelligence Overview
NVD
CVE.org
EPSS
VulDB
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
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
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.
Affected Products (CPE)CVE.org
GNU Bash through 4.3 processes trailing strings after function definitions in the values of environment variables, which
GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables, whi
GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed function definitions in the values of
Off-by-one error in the read_token_word function in parse.y in GNU Bash through 4.3 bash43-026 allows remote attackers t
The redirection implementation in parse.y in GNU Bash through 4.3 bash43-026 allows remote attackers to cause a denial o
GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables, whi
An issue was discovered in disable_priv_mode in shell.c in GNU Bash through 5.0 patch 11. Rated high severity (CVSS 7.8)
Bash before 4.4 allows local users to execute arbitrary commands with root privileges via crafted SHELLOPTS and PS4 envi
The expansion of '\h' in the prompt string in bash 4.3 allows remote authenticated users to execute arbitrary code via s
rbash in Bash before 4.4-beta2 did not prevent the shell user from modifying BASH_CMDS, thus allowing the user to execut
The path autocompletion feature in Bash 4.4 allows local users to gain privileges via a crafted filename starting with a
Stack-based buffer overflow in lib/sh/eaccess.c in GNU Bash before 4.2 patch 33 might allow local users to bypass intend
GitHub PoC
Exploit-DB