CVE-2026-73639

Imager::File::PNG versions from 1.003 before 1.004 for Perl write past the end of the row buffer reading a PNG with a tRNS transparency chunk in read_direct8. With a tRNS chunk, read_direct8() adds an alpha channel to the image it creates but still sizes the row buffer from the original channel count. libpng expands the transparency into that extra channel, so png_read_row() fills one channel more than the buffer holds, at one byte per sample, and writes width bytes past the end of the allocation. Palette images go to read_paletted() and 16-bit images to read_direct16(), which sizes its buffer from png_get_rowbytes() and allocates enough for the expanded row. The same reader ships bundled in the Imager distribution. Reading an attacker-supplied PNG through Imager->read() corrupts the heap, which can crash the process.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/tonycoz/imager/commit/d973bd7e8843f084e8071caa24b89545c88b1e4b.patch
https://github.com/tonycoz/imager/pull/567
https://github.com/tonycoz/imager/security/advisories/GHSA-jhx5-34j8-9g88
https://metacpan.org/release/TONYC/Imager-1.035/changes
https://metacpan.org/release/TONYC/Imager-File-PNG-1.004/changes
http://www.openwall.com/lists/oss-security/2026/09/17/6

Configurations

No configuration.

History

22 Sep 2026, 19:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.1

18 Sep 2026, 01:16

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/09/17/6 -

17 Sep 2026, 22:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 22:17

Updated : 2026-09-22 19:16

NVD link : CVE-2026-73639

Mitre link : CVE-2026-73639

CVE.ORG link : CVE-2026-73639

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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