Out-of-bounds Read in Mchehab Zbar
CVE-2026-121942
ZBar through 0.23.95 contains an out-of-bounds read vulnerability in _zbar_sq_decode() in zbar/sqcode.c that allows attackers to read heap memory outside the image buffer via crafted SQ code images. Attackers can supply an image with a skewed SQ code finder pattern near the edge, producing unchecked sample coordinates that crash the decoder and leak bytes into output.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/mchehab/zbar/issues/351 (issue-tracking)
- hackmd.io/@haindpwn/zbar-sqcode-sampling-oob-read (third-party-advisory)
- github.com/mchehab/zbar/blob/0.23.95/zbar/sqcode.c (technical-description)
- www.vulncheck.com/advisories/zbar-through-0.23.95-out-of-bounds-read-via-zbar-s… (third-party-advisory)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0
Frequently asked questions
- What is CVE-2026-121942?
- CVE-2026-121942 is a medium-severity vulnerability in Mchehab Zbar, classified under Out-of-bounds Read. CVSS score: 6.1/10. Published 2026-11-04.
- How severe is CVE-2026-121942?
- Medium severity. CVSS v3 base score is 6.1 out of 10.