Vulnerability in Libarchive
CVE-2021-23177
An improper link resolution flaw while extracting an archive can lead to changing the access control list (ACL) of the target of the link. An attacker may provide a malicious archive to a victim user, who would trigger this flaw when trying to extract the archive. A local attacker may use this flaw to change the ACL of a file on the system and gain more privileges.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.004 (31.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 31.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: +0.000
Affected products
- Libarchive
- Debian Linux — versions 10.0
- Fedoraproject Fedora — versions 35
- Red Hat Codeready Linux Builder
- Red Hat Enterprise Linux — versions 8.0
- Red Hat Enterprise Linux Eus — versions 8.6
- Red Hat Enterprise Linux For IBM Z Systems — versions 8.0
- Red Hat Enterprise Linux For IBM Z Systems Eus — versions 8.6
- Red Hat Enterprise Linux For Power Little Endian — versions 8.0
- Red Hat Enterprise Linux For Power Little Endian Eus — versions 8.6
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/libarchive/libarchive/issues/1565 (Patch, Third Party Advisory, Issue Tracking)
- github.com/libarchive/libarchive/commit/fba4f123cc456d2b2538f811bb831483bf336bad (Patch, Third Party Advisory)
- bugzilla.redhat.com/show_bug.cgi (Patch, Third Party Advisory, Issue Tracking)
- access.redhat.com/security/cve/CVE-2021-23177 (Third Party Advisory)
- lists.debian.org/debian-lts-announce/2022/11/msg00030.html (mailing-list, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-23177?
- CVE-2021-23177 is a high-severity vulnerability in Libarchive, classified under Improper Link Resolution Before File Access. CVSS score: 7.8/10. Published 2022-08-23.
- How severe is CVE-2021-23177?
- High severity. CVSS v3 base score is 7.8 out of 10.
- Is CVE-2021-23177 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.