Amazon Linux 2023 Security Advisory: ALAS2023-2026-1554
Advisory Released Date: 2026-04-13
Advisory Updated Date: 2026-04-13
FAQs regarding Amazon Linux ALAS/CVE Severity
LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. In versions 1.2.1 through 1.6.55, `png_set_tRNS` and `png_set_PLTE` each alias a heap-allocated buffer between `png_struct` and `png_info`, sharing a single allocation across two structs with independent lifetimes. The `trans_alpha` aliasing has been present since at least libpng 1.0, and the `palette` aliasing since at least 1.2.1. Both affect all prior release lines `png_set_tRNS` sets `png_ptr->trans_alpha = info_ptr->trans_alpha` (256-byte buffer) and `png_set_PLTE` sets `info_ptr->palette = png_ptr->palette` (768-byte buffer). In both cases, calling `png_free_data` (with `PNG_FREE_TRNS` or `PNG_FREE_PLTE`) frees the buffer through `info_ptr` while the corresponding `png_ptr` pointer remains dangling. Subsequent row-transform functions dereference and, in some code paths, write to the freed memory. A second call to `png_set_tRNS` or `png_set_PLTE` has the same effect, because both functions call `png_free_data` internally before reallocating the `info_ptr` buffer. Version 1.6.56 fixes the issue.
NOTE: https://github.com/pnggroup/libpng/security/advisories/GHSA-m4pc-p4q3-4c7j
NOTE: https://github.com/pnggroup/libpng/pull/824
NOTE: Fixed by: https://github.com/pnggroup/libpng/commit/23019269764e35ed8458e517f1897bd3c54820eb (v1.6.56)
NOTE: Fixed by: https://github.com/pnggroup/libpng/commit/a3a21443ed12bfa1ef46fa0d4fb2b74a0fa34a25 (v1.6.56)
NOTE: Fixed by: https://github.com/pnggroup/libpng/commit/7ea9eea884a2328cc7fdcb3c0c00246a50d90667 (v1.6.56)
NOTE: Fixed by: https://github.com/pnggroup/libpng/commit/c1b0318b393c90679e6fa5bc1d329fd5d5012ec1 (v1.6.56) (CVE-2026-33416)
LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network Graphics) raster image files. In versions 1.6.36 through 1.6.55, an out-of-bounds read and write exists in libpng's ARM/AArch64 Neon-optimized palette expansion path. When expanding 8-bit paletted rows to RGB or RGBA, the Neon loop processes a final partial chunk without verifying that enough input pixels remain. Because the implementation works backward from the end of the row, the final iteration dereferences pointers before the start of the row buffer (OOB read) and writes expanded pixel data to the same underflowed positions (OOB write). This is reachable via normal decoding of attacker-controlled PNG input if Neon is enabled. Version 1.6.56 fixes the issue.
NOTE: https://github.com/pnggroup/libpng/security/advisories/GHSA-wjr5-c57x-95m2
NOTE: Introduced with: https://github.com/pnggroup/libpng/commit/7734cda20cf1236aef60f3bbd2267c97bbb40869 (v1.6.36)
NOTE: Fixed by: https://github.com/pnggroup/libpng/commit/aba9f18eba870d14fb52c5ba5d73451349e339c3 (v1.6.56) (CVE-2026-33636)
Race condition, use-after-free in the Graphics: WebRender component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4684)
Incorrect boundary conditions in the Graphics: Canvas2D component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4685)
Incorrect boundary conditions in the Graphics: Canvas2D component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4686)
Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4687)
Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4688)
Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4689)
Sandbox escape due to incorrect boundary conditions, integer overflow in the XPCOM component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4690)
Use-after-free in the CSS Parsing and Computation component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4691)
Sandbox escape in the Responsive Design Mode component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4692)
Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4693)
Incorrect boundary conditions, integer overflow in the Graphics component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4694)
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4695)
Use-after-free in the Layout: Text and Fonts component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4696)
Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4697)
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4698)
Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4699)
Mitigation bypass in the Networking: HTTP component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4700)
Use-after-free in the JavaScript Engine component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4701)
JIT miscompilation in the JavaScript Engine component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4702)
Denial-of-service in the WebRTC: Signaling component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4704)
Undefined behavior in the WebRTC: Signaling component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4705)
Incorrect boundary conditions in the Graphics: Canvas2D component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4706)
Incorrect boundary conditions in the Graphics: Canvas2D component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4707)
Incorrect boundary conditions in the Graphics component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4708)
Incorrect boundary conditions in the Audio/Video: GMP component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4709)
Incorrect boundary conditions in the Audio/Video component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4710)
Use-after-free in the Widget: Cocoa component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4711)
Information disclosure in the Widget: Cocoa component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4712)
Incorrect boundary conditions in the Graphics component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4713)
Incorrect boundary conditions in the Audio/Video component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4714)
Uninitialized memory in the Graphics: Canvas2D component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4715)
Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4716)
Privilege escalation in the Netmonitor component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4717)
Undefined behavior in the WebRTC: Signaling component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4718)
Incorrect boundary conditions in the Graphics: Text component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4719)
Memory safety bugs present in Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9. (CVE-2026-4720)
Memory safety bugs present in Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. (CVE-2026-4721)
Affected Packages:
firefox
Issue Correction:
Run dnf update firefox --releasever 2023.11.20260413 or dnf update --advisory ALAS2023-2026-1554 --releasever 2023.11.20260413 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation
aarch64:
firefox-debuginfo-140.9.0-1.amzn2023.0.2.aarch64
firefox-140.9.0-1.amzn2023.0.2.aarch64
firefox-debugsource-140.9.0-1.amzn2023.0.2.aarch64
src:
firefox-140.9.0-1.amzn2023.0.2.src
x86_64:
firefox-debuginfo-140.9.0-1.amzn2023.0.2.x86_64
firefox-140.9.0-1.amzn2023.0.2.x86_64
firefox-debugsource-140.9.0-1.amzn2023.0.2.x86_64