CVE-2026-39373 (GCVE-0-2026-39373)
Vulnerability from cvelistv5
Published
2026-04-07 19:35
Modified
2026-04-07 20:22
Severity ?
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Summary
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.
References
Impacted products
Vendor Product Version
latchset jwcrypto Version: < 1.5.7
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