Bash
CVE-2016-0634
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization OS command sanitization, avoid shell exec
MITRE ATT&CK
2 techniques across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, high complexity, low privileges required, no user interaction not required. EPSS exploitation probability: 2.78%. |
| Exploit ScenarioDerived | A remote attacker could execute arbitrary operating system commands on the host by sending crafted requests to the affected application. |
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Alert meAnalysisAI
The expansion of '\h' in the prompt string in bash 4.3 allows remote authenticated users to execute arbitrary code via shell metacharacters placed in 'hostname' of a machine. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable. This OS Command Injection vulnerability could allow attackers to execute arbitrary operating system commands on the host.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Avoid passing user input to shell commands. Use language-specific APIs instead of shell execution. Apply strict input validation with allowlists.
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 OS Command Injection (CWE-78), which allows attackers to execute arbitrary operating system commands on the host. The expansion of '\h' in the prompt string in bash 4.3 allows remote authenticated users to execute arbitrary code via shell metacharacters placed in 'hostname' of a machine. Affected products include: Gnu Bash.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
The expansion of '\h' in the prompt string in bash 4.3 allows remote authenticated users to execute arbitrary code via shell metacharacters placed in 'hostname' of a machine.
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
OS command injection occurs when an application passes unsanitized user input directly into system shell commands.
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
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
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
popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address. Ra
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