Amazon Linux 2023 Security Advisory: ALAS2023-2026-1590
Advisory Released Date: 2026-04-30
Advisory Updated Date: 2026-04-30
Severity:
Important
Issue Overview:
JWCrypto implements JWK, JWS, and JWE specifications using python-cryptography. Prior to 1.5.7, an unauthenticated attacker can exhaust server memory by sending crafted JWE tokens with ZIP compression. The existing patch for CVE-2024-28102 limits input token size to 250KB but does not validate the decompressed output size. An unauthenticated attacker can cause memory exhaustion on memory-constrained systems. A token under the 250KB input limit can decompress to approximately 100MB. This vulnerability is fixed in 1.5.7. (CVE-2026-39373)
Affected Packages:
python-jwcrypto
Issue Correction:
Run dnf update python-jwcrypto --releasever 2023.11.20260427 or dnf update --advisory ALAS2023-2026-1590 --releasever 2023.11.20260427 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation
New Packages:
noarch:
python3-jwcrypto-1.4.2-46.amzn2023.0.1.noarch
src:
python-jwcrypto-1.4.2-46.amzn2023.0.1.src