A reachable assertion vulnerability exists in YARA 4.5.8 when loading crafted .yrc compiled rule files.

published 2026-09-22 48 d ago modified 2026-09-24 45 d ago also EUVD-2026-84850

cvss: 5.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 4%
public exploits: 0; none known

A reachable assertion vulnerability exists in YARA 4.5.8 when loading crafted .yrc compiled rule files. An attacker can provide a malicious file with an invalid arena configuration (num_buffers=0) that triggers an assertion failure in yr_arena_get_ptr(), causing the application to terminate.

Patch / fix

links 1

github.com/NOUIY/yara@0cdff36 commit

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-88341 updated 2026-11-06 cvss 5.0

yara: YARA: Denial of Service via crafted compiled rule file

Red Hat Enterprise Linux 8 yara Red Hat Enterprise Linux 9 yara Red Hat Enterprise Linux 10 yara
affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 46 d ago (2026-09-23)

Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/VirusTotal/yara/issues/2238 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CNA	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Classification

Weakness

CWE-617 Reachable Assertion

References

Sources

CVE List CVE-2026-88341
NVD CVE-2026-88341

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary