PT-2022-10744 · Linux+1 · Linux Kernel+1

Itai Greenhut · Published 2022-08-26 · Updated 2026-04-20 · CVE-2021-3864

Positive Technologies (AI Summary)

CVSS v3.1

7.0

High

Base vector

AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description 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.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Improper Access Control

Weakness Enumeration

CWE-284

Related Identifiers

CVE-2021-3864

ECHO-8FC4-384E-057A

Affected Products

Debian

Linux Kernel

References · 22

• 🔥 https://openwall.com/lists/oss-security/2021/10/20/2 · Exploit
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-13-CVE-2021-3864 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2021-3864 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2021-3864 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2021-3864 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-3864 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2021-3864 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-3864 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2404-CVE-2021-3864 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-11-CVE-2021-3864 · Vendor Advisory
• https://bugzilla.redhat.com/show_bug.cgi?id=2015046 · Patch
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-12-CVE-2021-3864 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2204-CVE-2021-3864 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-3864 · Vendor Advisory
• https://lore.kernel.org/lkml/20211228170910.623156-1-wander%40redhat.com · Note