CVE-2026-39373

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/latchset/jwcrypto/security/advisories/GHSA-fjrm-76x2-c4q4	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:latchset:jwcrypto:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-07 20:16

Updated : 2026-07-24 21:10

NVD link : CVE-2026-39373

Mitre link : CVE-2026-39373

CVE.ORG link : CVE-2026-39373

JSON object : View

Products Affected

latchset

jwcrypto

CWE

CWE-409

Improper Handling of Highly Compressed Data (Data Amplification)

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