ZBar commit 2ea2ca58 contains an undefined-behavior vulnerability in the Code 128 decode6() function.

published 2026-09-24 46 d ago modified 2026-10-06 33 d ago also EUVD-2026-86270

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 5%
public exploits: 0; none known

ZBar commit 2ea2ca58 contains an undefined-behavior vulnerability in the Code 128 decode6() function. When processing specially crafted Code 128 input, decode_e() can return -1 for an invalid edge pattern, and decode6() subsequently left-shifts this negative signed value while constructing the edge signature. The operation invokes undefined behavior and can terminate trap-mode UBSan builds with SIGILL, resulting in denial of service.

Patch / fix

distros 2

debian opensuse

zbar Debian 14 0.23.95-1

debian advisories DEBIAN-CVE-2026-88371

zbar openSUSE Tumbleweed 0.23.95-2.1

opensuse advisories openSUSE-SU-2026:12146-1

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-2026-88371 updated 2026-09-29 cvss 5.5

zbar: zbar: Denial of Service via crafted Code 128 barcode input

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

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: 34 d ago (2026-10-06)

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/mchehab/zbar/issues/336 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-682 Incorrect Calculation

References

github.com /mchehab/zbar/issues/336
exploit

Sources

CVE List CVE-2026-88371
NVD CVE-2026-88371

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