Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

Go to Calendar     Go to Press Room     Go to Newsletters subscription

Search

CVE-2019-18276

Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
28/11/2019
Last modified:
09/06/2025

Description

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.

Impact

Vector 3.x
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.80 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x
7.80
Severity 3.x
HIGH
Vector 2.0
AV:L/AC:L/Au:N/C:C/I:C/A:C CVSS v2.0 Severity and Metrics:

Base Score: 7.20 HIGH
Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C

Attack Vector (AV): Local
Attack Complexity (AC): Low
Authentication (Au): None
Confidentiality (C): Complete
Integrity (I): Complete
Availability (A): Complete

Base Score 2.0
7.20
Severity 2.0
HIGH

Vulnerable products and versions

CPE From Up to
cpe:2.3:a:gnu:bash:*:*:*:*:*:*:*:* 5.0 (including)
cpe:2.3:a:gnu:bash:5.0:beta1:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:beta2:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch1:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch10:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch11:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch2:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch3:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch4:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch5:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch6:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch7:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch8:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:patch9:*:*:*:*:*:*
cpe:2.3:a:gnu:bash:5.0:rc1:*:*:*:*:*:*

To consult the complete list of CPE names with products and versions, see this page


References to Advisories, Solutions, and Tools