SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-4424

This heap out-of-bounds read vulnerability exists in the RAR archive processing logic due to improper validation of the LZSS sliding window size after transitions between compression methods.

HIGH 7.5EPSS 1.26%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.26%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A flaw was found in libarchive. This heap out-of-bounds read vulnerability exists in the RAR archive processing logic due to improper validation of the LZSS sliding window size after transitions between compression methods. A remote attacker can exploit this by providing a specially crafted RAR archive, leading to the disclosure of sensitive heap memory information without requiring authentication or user interaction.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS
1.26% probability · 69th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-125
Affected
libarchive/libarchive · redhat/hardened images · redhat/openshift container platform · redhat/openshift container platform for arm64 · redhat/openshift container platform for power · redhat/enterprise linux · redhat/enterprise linux server aus
Source
secalert@redhat.com
EPSS trend
0%3%5%26 October 2026: 1.26%26 October 202626 October 2026

EPSS 1.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.