Quick answers
- Is CVE-2026-12912 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-12912 being exploited in the wild.
- How severe is CVE-2026-12912?
- High severity, with a CVSS score of 7.3, published 29 June 2026.
- Which products and versions are affected?
- Libtiff 4.7.1.
- Is there a fix for CVE-2026-12912?
- A patch was published on 2026-04-23: Merge request 873 created to address the issue Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-12912 attacked?
- It is attacked with local access, in a software library.
- Am I affected by CVE-2026-12912?
- Check whether you run Libtiff at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A heap-based buffer overflow (CWE-122) exists in libtiff's PixarLog codec, specifically within the `horizontalAccumulate8abgr` function and `PixarLogDecode` in `tif_pixarlog.c`. The flaw is triggered when decoding images with `PIXARLOGDATAFMT_8BITABGR` output format and a stride of 3. In this configuration, the decoder writes 4 bytes per 3 decoded samples (adding a synthetic alpha byte) but incorrectly advances the output cursor by only 3 bytes. This pointer mismatch results in a linear overflow of approximately 'width' bytes per scanline. An attacker can exploit this by providing a crafted TIFF image to an application that utilizes these specific libtiff fields, potentially achieving arbitrary code execution. A fix involving corrected pointer advancement and scanline size overrides has been proposed in the libtiff GitLab repository.
Affected products
- libtiff libtiff 4.7.1
- Red Hat Red Hat Enterprise Linux 7
- Red Hat Red Hat Enterprise Linux 8
- Red Hat Red Hat Enterprise Linux 9
- Red Hat Red Hat Enterprise Linux 10
Timeline
- 2026-04-23: patched: Merge request 873 created to address the issue
- 2026-06-25: disclosed: Initial report to Red Hat Bugzilla
- 2026-06-29: advisory: CVE published by Red Hat