Amazon Linux 2 Security Advisory: ALAS2-2026-3281
Advisory Released Date: 2026-05-14
Advisory Updated Date: 2026-05-14
Mitgation of CVE-2026-4519 was incomplete. If the URL contained "%action" the mitigation could be bypassed for certain browser types the "webbrowser.open()" API could have commands injected into the underlying shell. See CVE-2026-4519 for details. (CVE-2026-4786)
Use-after-free (UAF) was possible in the `lzma.LZMADecompressor`, `bz2.BZ2Decompressor`, and `gzip.GzipFile` when a memory allocation fails with a `MemoryError` and the decompression instance is re-used. This scenario can be triggered if the process is under memory pressure. The fix cleans up the dangling pointer in this specific error condition.
The vulnerability is only present if the program re-uses decompressor instances across multiple decompression calls even after a `MemoryError` is raised during decompression. Using the helper functions to one-shot decompress data such as `lzma.decompress()`, `bz2.decompress()`, `gzip.decompress()`, and `zlib.decompress()` are not affected as a new decompressor instance is used per call. If the decompressor instance is not re-used after an error condition, this usage is similarly not vulnerable. (CVE-2026-6100)
Affected Packages:
python3
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update python3 or yum update --advisory ALAS2-2026-3281 to update your system.
aarch64:
python3-3.7.16-1.amzn2.0.26.aarch64
python3-libs-3.7.16-1.amzn2.0.26.aarch64
python3-devel-3.7.16-1.amzn2.0.26.aarch64
python3-tools-3.7.16-1.amzn2.0.26.aarch64
python3-tkinter-3.7.16-1.amzn2.0.26.aarch64
python3-test-3.7.16-1.amzn2.0.26.aarch64
python3-debug-3.7.16-1.amzn2.0.26.aarch64
python3-debuginfo-3.7.16-1.amzn2.0.26.aarch64
i686:
python3-3.7.16-1.amzn2.0.26.i686
python3-libs-3.7.16-1.amzn2.0.26.i686
python3-devel-3.7.16-1.amzn2.0.26.i686
python3-tools-3.7.16-1.amzn2.0.26.i686
python3-tkinter-3.7.16-1.amzn2.0.26.i686
python3-test-3.7.16-1.amzn2.0.26.i686
python3-debug-3.7.16-1.amzn2.0.26.i686
python3-debuginfo-3.7.16-1.amzn2.0.26.i686
src:
python3-3.7.16-1.amzn2.0.26.src
x86_64:
python3-3.7.16-1.amzn2.0.26.x86_64
python3-libs-3.7.16-1.amzn2.0.26.x86_64
python3-devel-3.7.16-1.amzn2.0.26.x86_64
python3-tools-3.7.16-1.amzn2.0.26.x86_64
python3-tkinter-3.7.16-1.amzn2.0.26.x86_64
python3-test-3.7.16-1.amzn2.0.26.x86_64
python3-debug-3.7.16-1.amzn2.0.26.x86_64
python3-debuginfo-3.7.16-1.amzn2.0.26.x86_64