# CVE-2026-121942: ZBar through 0.23.95 Out-of-Bounds Read via _zbar_sq_decode() in sqcode.c

Status: published. Published: 2026-11-04. Updated: 2026-11-04.

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.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- mchehab / zbar (mchehab/zbar): ≥ 0; ≤ 0.23.95 (affected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 6.9 (medium); CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 6.1 (medium); CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-125

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/mchehab/zbar/issues/351 (CNA: VulnCheck; issue-tracking)

- https://hackmd.io/@haindpwn/zbar-sqcode-sampling-oob-read (CNA: VulnCheck; third-party-advisory)

- https://github.com/mchehab/zbar/blob/0.23.95/zbar/sqcode.c#L529-L567 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/zbar-through-0.23.95-out-of-bounds-read-via-zbar-sq-decode-in-sqcode-c (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-121942; retrieved 2026-11-04; source updated 2026-11-04

Revision: 301d77aff67cfd5c4c86b63e4b1033fbb91e6457378ce907dd00b92acc1588be

Canonical: https://y2.dev/cve/CVE-2026-121942

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