# CVE-2026-73638: Imager out-of-bounds read in TIFF IFD parsing

Source: https://junglewise.ai/threats/cve-2026-73638-imager-out-of-bounds-read-in-tiff-ifd-parsing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-17. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-73638 · Severity: medium · CVSS 6.2 · Published 2026-09-17

Imager is a Perl image processing library used to read and manipulate image files. A flaw in its TIFF file parsing allows attackers to craft malicious TIFF files that cause the library to read data outside allocated memory buffers, potentially exposing sensitive information or crashing applications that process untrusted images.

## Quick answers

**Is CVE-2026-73638 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-73638 being exploited in the wild.

**How severe is CVE-2026-73638?** Medium severity, with a CVSS score of 6.2, published 17 September 2026.

**Which products and versions are affected?** Tony Bowden Imager 0.45_02 to before 1.035.

**Is there a fix for CVE-2026-73638?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-73638 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-73638?** Check whether anything you run is named in the advisory. 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

The vulnerability exists in the tiff_load_ifd() function, which parses TIFF Image File Directory (IFD) entries. The validator checks that the sum of an entry's offset and size stays within the EXIF block, but fails to validate the start offset itself. On 32-bit systems and 64-bit Windows (where size_t or unsigned long are 32 bits), integer wrap-around can cause the bounds check to pass when an entry actually starts or extends outside the intended block. The field type changed from int (vulnerable to sign-bit wrapping in versions ≤1.032) to size_t (vulnerable to unsigned wrap on 32-bit systems in versions ≥1.033). Any application calling Imager->read() on attacker-supplied TIFF images can leak EXIF data from outside the block or crash.

## Affected products

- Tony Bowden Imager 0.45_02 to before 1.035

## Timeline

- 2026-09-17: disclosed
- 2026-09-17: advisory

## References

- [https://cpan.org/modules](https://cpan.org/modules)
- [https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1144226](https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1144226)