CVE-2026-34757
Publication date 9 April 2026
Last updated 16 April 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libpng | 25.10 questing | Not in release |
| 24.04 LTS noble | Not in release | |
| 22.04 LTS jammy | Not in release | |
| 16.04 LTS xenial |
Needs evaluation
|
|
| 14.04 LTS trusty |
Needs evaluation
|
|
| libpng1.6 | 25.10 questing |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Needs evaluation
|
|
| firefox | 25.10 questing |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| thunderbird | 25.10 questing |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| chromium-browser | 25.10 questing |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
Notes
mdeslaur
Per the upstream developer Cosmin Truta, the fix for this CVE is 398cbe3d, but 55d20aaa and 2c974860 are also security issues that should be fixed at the same time. The only difference between 1.6.56 and 1.6.57 are those 3 changes, and upstream has requested that resolute be updated to the new version rather than having the fix for this CVE backported.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
5.1 · Medium
|
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | Low |
| Integrity impact | Low |
| Availability impact | None |
| Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |