5.5

CVE-2026-5745: libarchive NULL Pointer Dereference

CVSS: 5.5v3.1MediumModified
AliasesUBUNTU-CVE-2026-5745DEBIAN-CVE-2026-5745CGA-72vq-cvx6-c2x8
Published 07-04-2026Last modified 01-09-2026
Open JSON

Vulnerability summary

CVE-2026-5745 is a medium (CVSS 5.5) NULL Pointer Dereference vulnerability in libarchive. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.17%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3 · Related 2
MGASA-2026-0241MGASA-2026-0366RHSA-2026:8944CGA-2G8X-39FC-372WUSN-8581-1

Timeline

  1. 07-04-2026
    PublishedVulnerability first disclosed.
  2. 01-09-2026
    Last modifiedVulnerability information updated.

Description

A flaw was found in libarchive. A NULL pointer dereference vulnerability exists in the ACL parsing logic, specifically within the archive_acl_from_text_nl() function. When processing a malformed ACL string (such as a bare "d" or "default" tag without subsequent fields), the function fails to perform adequate validation before advancing the pointer. An attacker can exploit this by providing a maliciously crafted archive, causing an application utilizing the libarchive API (such as bsdtar) to crash, resulting in a Denial of Service (DoS).

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.17%

Chance of exploitation in the next 30 days

Percentile

6%

Versus all other CVEs

30-day change

+0.01 pp

From 0.16% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.17%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard4 products
  • libarchiveAll versions (No fix recorded)
  • libarchive-devAll versions (No fix recorded)
  • libarchive-docAll versions (No fix recorded)
  • libarchive-toolsAll versions (No fix recorded)
Wolfi4 products
  • libarchiveAll versions (No fix recorded)
  • libarchive-devAll versions (No fix recorded)
  • libarchive-docAll versions (No fix recorded)
  • libarchive-toolsAll versions (No fix recorded)
Redhat3 products
Debian1 product
  • libarchiveAll versions (No fix recorded) | < 3.8.8-1
Libarchive1 product
Ubuntu1 product
  • libarchive< 3.4.0-2ubuntu1.5+esm3 | < 3.6.0-1ubuntu1.8 | < 3.7.2-2ubuntu0.8 | All versions (No fix recorded) | < 3.8.5-1ubuntu2.2

6 vendors · 14 products

References

7 links