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).
Affected products
libarchive: libarchive; redhat: hardened images; redhat: openshift container platform; redhat: enterprise linux
References3
- access.redhat.com/errata/RHSA-2026:8944
- access.redhat.com/security/cve/CVE-2026-5745 Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2455921 Issue TrackingThird Party Advisory
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 12 November 2026
- CWE
- CWE-476
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