What is CVE-2023-31580?

CVE-2023-31580 is a medium-severity vulnerability in Networknt Light-Oauth2, classified under Improper Certificate Validation. CVSS score: 5.9/10. Published 2023-10-25.

How severe is CVE-2023-31580?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Vulnerability in Networknt Light-Oauth2

CVE-2023-31580

light-oauth2 before version 2.1.27 obtains the public key without any verification. This could allow attackers to authenticate to the application with a crafted JWT token.

Vulnerability class: Improper Certificate Validation

Published 2023-10-25 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (44.1th percentile), scored 2026-10-05.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Networknt Light-Oauth2

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

References

github.com/networknt/light-oauth2/issues/369 (Issue Tracking)
github.com/KANIXB/JWTIssues/blob/main/Certification Verification issue in light… (Exploit)

Frequently asked questions

What is CVE-2023-31580?: CVE-2023-31580 is a medium-severity vulnerability in Networknt Light-Oauth2, classified under Improper Certificate Validation. CVSS score: 5.9/10. Published 2023-10-25.
How severe is CVE-2023-31580?: Medium severity. CVSS v3 base score is 5.9 out of 10.