ALAS2-2026-3280


Amazon Linux 2 Security Advisory: ALAS2-2026-3280
Advisory Released Date: 2026-05-14
Advisory Updated Date: 2026-05-14
Severity: Important

Issue Overview:

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:

python


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 python or yum update --advisory ALAS2-2026-3280 to update your system.

New Packages:
aarch64:
    python-2.7.18-1.amzn2.0.19.aarch64
    python-libs-2.7.18-1.amzn2.0.19.aarch64
    python-devel-2.7.18-1.amzn2.0.19.aarch64
    python-tools-2.7.18-1.amzn2.0.19.aarch64
    tkinter-2.7.18-1.amzn2.0.19.aarch64
    python-test-2.7.18-1.amzn2.0.19.aarch64
    python-debug-2.7.18-1.amzn2.0.19.aarch64
    python-debuginfo-2.7.18-1.amzn2.0.19.aarch64

i686:
    python-2.7.18-1.amzn2.0.19.i686
    python-libs-2.7.18-1.amzn2.0.19.i686
    python-devel-2.7.18-1.amzn2.0.19.i686
    python-tools-2.7.18-1.amzn2.0.19.i686
    tkinter-2.7.18-1.amzn2.0.19.i686
    python-test-2.7.18-1.amzn2.0.19.i686
    python-debug-2.7.18-1.amzn2.0.19.i686
    python-debuginfo-2.7.18-1.amzn2.0.19.i686

src:
    python-2.7.18-1.amzn2.0.19.src

x86_64:
    python-2.7.18-1.amzn2.0.19.x86_64
    python-libs-2.7.18-1.amzn2.0.19.x86_64
    python-devel-2.7.18-1.amzn2.0.19.x86_64
    python-tools-2.7.18-1.amzn2.0.19.x86_64
    tkinter-2.7.18-1.amzn2.0.19.x86_64
    python-test-2.7.18-1.amzn2.0.19.x86_64
    python-debug-2.7.18-1.amzn2.0.19.x86_64
    python-debuginfo-2.7.18-1.amzn2.0.19.x86_64