Amazon Linux 2 (EOS) Security Advisory: ALAS2-2026-4033
Advisory Released Date: 2026-10-24
Advisory Updated Date: 2026-10-26
Severity:
Important
Issue Overview:
Tornado versions before 6.5.9 contain an unbounded memory accumulation vulnerability in CurlAsyncHTTPClient that allows remote attackers to cause denial of service by sending a compressed response. Attackers can send a gzip-encoded decompression bomb that accumulates in memory without size limits, causing the application process to be killed by out-of-memory conditions. (CVE-2026-103262)
Affected Packages:
python3-tornado
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-tornado or yum update --advisory ALAS2-2026-4033 to update your system.
New Packages:
aarch64:
python3-tornado-5.0.2-4.amzn2.0.12.aarch64
python3-tornado-doc-5.0.2-4.amzn2.0.12.aarch64
python3-tornado-debuginfo-5.0.2-4.amzn2.0.12.aarch64
i686:
python3-tornado-5.0.2-4.amzn2.0.12.i686
python3-tornado-doc-5.0.2-4.amzn2.0.12.i686
python3-tornado-debuginfo-5.0.2-4.amzn2.0.12.i686
src:
python3-tornado-5.0.2-4.amzn2.0.12.src
x86_64:
python3-tornado-5.0.2-4.amzn2.0.12.x86_64
python3-tornado-doc-5.0.2-4.amzn2.0.12.x86_64
python3-tornado-debuginfo-5.0.2-4.amzn2.0.12.x86_64