CVE-2026-39373 (GCVE-0-2026-39373)

Vulnerability from cvelistv5 – Published: 2026-04-07 19:35 – Updated: 2026-04-07 20:22
VLAI
Title
JWCrypto: JWE ZIP decompression bomb
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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-07 20:22 UTC
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
latchset jwcrypto Affected: < 1.5.7
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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