CVE-2026-5121: Libarchive: libarchive: arbitrary code execution via integer overflow in iso9660 image processing

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-30 · updated 2026-10-14
Weakness: CWE-190

Description

A flaw was found in libarchive. On 32-bit systems, an integer overflow vulnerability exists in the zisofs block pointer allocation logic. A remote attacker can exploit this by providing a specially crafted ISO9660 image, which can lead to a heap buffer overflow. This could potentially allow for arbitrary code execution on the affected system.

Affected products

libarchive: all versions
Red Hat Enterprise Linux: 6.0, 7.0, 8.0, 9.0, 10.0
RedHat Hardened Images: all versions
Red Hat OpenShift Container Platform 4.18: 4.0

References

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