Skip to main content

Bash CVE-2019-18276

HIGH
Improper Check for Dropped Privileges (CWE-273)
2019-11-28 cve@mitre.org
7.8
CVSS 3.1 · NVD
Share

Severity by source

NVD PRIMARY
7.8 HIGH
AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Lifecycle Timeline

1
CVE Published
Nov 28, 2019 - 01:15 nvd
HIGH 7.8

DescriptionNVD

An issue was discovered in disable_priv_mode in shell.c in GNU Bash through 5.0 patch 11. By default, if Bash is run with its effective UID not equal to its real UID, it will drop privileges by setting its effective UID to its real UID. However, it does so incorrectly. On Linux and other systems that support "saved UID" functionality, the saved UID is not dropped. An attacker with command execution in the shell can use "enable -f" for runtime loading of a new builtin, which can be a shared object that calls setuid() and therefore regains privileges. However, binaries running with an effective UID of 0 are unaffected.

AnalysisAI

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), this vulnerability is low attack complexity. Public exploit code available.

Technical ContextAI

This vulnerability is classified under CWE-273. An issue was discovered in disable_priv_mode in shell.c in GNU Bash through 5.0 patch 11. By default, if Bash is run with its effective UID not equal to its real UID, it will drop privileges by setting its effective UID to its real UID. However, it does so incorrectly. On Linux and other systems that support "saved UID" functionality, the saved UID is not dropped. An attacker with command execution in the shell can use "enable -f" for runtime loading of a new builtin, which can be a shared object that calls setuid() and therefore regains privileges. However, binaries running with an effective UID of 0 are unaffected. Affected products include: Gnu Bash, Netapp Hci Management Node, Netapp Oncommand Unified Manager, Netapp Solidfire, Oracle Communications Cloud Native Core Policy. Version information: through 5.0.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

More in Bash

View all

Share

CVE-2019-18276 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy