CVE-2026-34757

MEDIUM EPSS 9.4%
Published Apr 9, 20262mo ago · Modified Jun 17, 20261w ago
4.4 CVSS 3.1
Medium
Find Similar
Published Apr 9, 2026 2mo ago
Last Modified Jun 17, 2026 1w ago

Description

LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. From 1.0.9 to before 1.6.57, passing a pointer obtained from png_get_PLTE, png_get_tRNS, or png_get_hIST back into the corresponding setter on the same png_struct/png_info pair causes the setter to read from freed memory and copy its contents into the replacement buffer. The setter frees the internal buffer before copying from the caller-supplied pointer, which now dangles. The freed region may contain stale data (producing silently corrupted chunk metadata) or data from subsequent heap allocations (leaking unrelated heap contents into the chunk struct). This vulnerability is fixed in 1.6.57.

CVSS Details

Base Score
4.4
Exploitability
1.8
Impact
2.5
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Low
Integrity Low
Availability None

Threat Intelligence

EPSS Exploit Probability
9.4% percentile
Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-416 Use After Free Memory Safety

Affected Products 2

VendorProductVersionRange
libpnglibpng*≥1.0.9  –  <1.6.57
debiandebian_linux11.0any

References 6

  • github.com https://github.com/pnggroup/libpng/commit/398cbe3df03f4e11bb031e07f416dfdde3684e8a
    Patch
  • github.com https://github.com/pnggroup/libpng/commit/55d20aaa322c9274491cda82c5cd4f99b48c6bcc
    Patch
  • github.com https://github.com/pnggroup/libpng/issues/836
    ExploitIssue TrackingMitigation
  • github.com https://github.com/pnggroup/libpng/issues/837
    ExploitIssue TrackingMitigation
  • github.com https://github.com/pnggroup/libpng/security/advisories/GHSA-6fr7-g8h7-v645
    MitigationPatchVendor Advisory
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2026/05/msg00017.html
    Mailing ListThird Party Advisory

Remediation

  • github.com https://github.com/pnggroup/libpng/commit/398cbe3df03f4e11bb031e07f416dfdde3684e8a
    Patch
  • github.com https://github.com/pnggroup/libpng/commit/55d20aaa322c9274491cda82c5cd4f99b48c6bcc
    Patch
  • github.com https://github.com/pnggroup/libpng/security/advisories/GHSA-6fr7-g8h7-v645
    MitigationPatchVendor Advisory