PT-2026-31004 · Latchset · Jwcrypto

Published 2026-04-07 · Updated 2026-04-07 · CVE-2026-39373

NVD

CVSS v3.1

5.3

Medium

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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.

Fix

Weakness Enumeration

CWE-409

Related Identifiers

CVE-2026-39373

Affected Products

Jwcrypto

References · 2

• https://nvd.nist.gov/vuln/detail/CVE-2026-39373 · Security Note
• https://github.com/latchset/jwcrypto/security/advisories/GHSA-fjrm-76x2-c4q4 · Note