CVE-2021-3864

A flaw was found in the way the dumpable flag setting was handled when certain SUID binaries executed its descendants. The prerequisite is a SUID binary that sets real UID equal to effective UID, and real GID equal to effective GID. The descendant will then have a dumpable value set to 1. As a result, if the descendant process crashes and core_pattern is set to a relative value, its core dump is stored in the current directory with uid:gid permissions. An unprivileged local user with eligible root SUID binary could use this flaw to place core dumps into root-owned directories, potentially resulting in escalation of privileges.

CVSS v3.0 7.0 HIGH

7.0^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=2015046	Issue Tracking Patch Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/10/20/2	Exploit Mailing List Third Party Advisory
https://access.redhat.com/security/cve/CVE-2021-3864	Third Party Advisory
https://security-tracker.debian.org/tracker/CVE-2021-3864	Third Party Advisory
https://lore.kernel.org/all/20211221021744.864115-1-longman%40redhat.com/
https://lore.kernel.org/lkml/20211228170910.623156-1-wander%40redhat.com/
https://lore.kernel.org/all/20211226150310.GA992%401wt.eu/

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Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:debian:debian_linux:10.0:::::::*
	cpe:2.3:o:debian:debian_linux:11.0:::::::*

Configuration 3 (hide)

OR	cpe:2.3:o:redhat:enterprise_linux:7.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:6.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:9.0:::::::*

Information

Published : 2022-08-26 09:15

Updated : 2023-02-12 15:42

NVD link : CVE-2021-3864

Mitre link : CVE-2021-3864

JSON object : View

CWE

CWE-284

Improper Access Control

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Products Affected

debian

debian_linux

redhat

enterprise_linux

linux

linux_kernel

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