What is CVE-2026-39373?

CVE-2026-39373 is a medium-severity vulnerability in Latchset Jwcrypto, classified under Improper Handling of Highly Compressed Data (Data Amplification). CVSS score: 5.3/10. Published 2026-04-07.

How severe is CVE-2026-39373?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Latchset Jwcrypto

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…

EPSS: 0.001 (28.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Latchset Jwcrypto — versions < 1.5.7

Weakness classification (CWE)

CWE-409 — Improper Handling of Highly Compressed Data (Data Amplification)

References

https://github.com/latchset/jwcrypto/security/advisories/GHSA-fjrm-76x2-c4q4 (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-39373?: CVE-2026-39373 is a medium-severity vulnerability in Latchset Jwcrypto, classified under Improper Handling of Highly Compressed Data (Data Amplification). CVSS score: 5.3/10. Published 2026-04-07.
How severe is CVE-2026-39373?: Medium severity. CVSS v3 base score is 5.3 out of 10.