CVE-2026-33996

MEDIUMNVD 5.55.5
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.5 under NVD CVSS v3. EPSS exploit probability: 0.1%, top 95% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

LibJWT is a C JSON Web Token Library. Starting in version 3.0.0 and prior to version 3.3.0, the JWK parsing for RSA-PSS did not protect against a NULL value when expecting to parse JSON string values. A specially crafted JWK file could exploit this behavior by using integers in places where the code expected a string. This was fixed in v3.3.0. A workaround is available. Users importing keys through a JWK file should not do so from untrusted sources. Use the jwk2key tool to check for validity of a JWK file. Likewise, if possible, do not use JWK files with RSA-PSS keys.

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
5%
KEV
Not listed

Published

March 27, 2026

Last Modified

June 17, 2026

Advisory Details (2)

Auto-updated Aug 6, 2026
Patch available. Sources: github_commit, github.
github Patch Available

NULL/bounds validation in JWK octet and RSA PSS parsing · Advisory · benmcollins/libjwt · GitHub

Affected: v3.3.0. I made the mistake of releasing the fix before creating the vulnerability

https://github.com/benmcollins/libjwt/security/advisories/GHSA-ph96-hqpc-9f66
github_commit Patch Available

commit cfd890286fa4 (benmcollins/libjwt)

Patch available: benmcollins/libjwt v3.3.0 (contains commit cfd890286fa4)

https://github.com/benmcollins/libjwt/commit/cfd890286fa49ae61b534c937c9f0428b5c6034c

Affected Packages

(1 across 1 ecosystem)
Debian:14(1)
PackageVulnerable rangeFixed inDependents
libjwt33.2.2-1, 3.2.3-13.3.2-1

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 27× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 19:30 UTCEPSS rescore
  4. 2026-09-16 14:08 UTCEPSS rescore
  5. 2026-09-16 05:15 UTCEPSS rescore
  6. 2026-09-15 03:11 UTCEPSS rescore
  7. 2026-09-13 16:47 UTCEPSS rescore
  8. 2026-09-11 14:53 UTCEPSS rescore
  9. 2026-09-11 09:37 UTCEPSS rescore
  10. 2026-09-10 09:34 UTCEPSS rescore
  11. 2026-09-08 22:00 UTCEPSS rescore
  12. 2026-09-07 16:01 UTCEPSS rescore
  13. 2026-09-06 13:47 UTCEPSS rescore
  14. 2026-09-04 05:06 UTCEPSS rescore
  15. 2026-09-02 14:12 UTCEPSS rescore
  16. 2026-09-02 13:04 UTCOSV refresh
  17. 2026-09-01 13:53 UTCEPSS rescore
  18. 2026-09-01 04:39 UTCEPSS rescore
  19. 2026-08-30 19:17 UTCEPSS rescore
  20. 2026-08-30 01:22 UTCEPSS rescore
  21. 2026-08-28 21:41 UTCEPSS rescore
  22. 2026-08-27 14:25 UTCEPSS rescore
  23. 2026-08-26 14:46 UTCEPSS rescore
  24. 2026-08-25 13:49 UTCEPSS rescore
  25. 2026-08-24 14:17 UTCEPSS rescore
Show 34 more
  1. 2026-08-23 00:19 UTCEPSS rescore
  2. 2026-08-21 23:49 UTCEPSS rescore
  3. 2026-08-20 22:55 UTCEPSS rescore
  4. 2026-08-20 22:55 UTCEPSS rescore
  5. 2026-08-19 17:03 UTCEPSS rescore
  6. 2026-08-18 13:48 UTCEPSS rescore
  7. 2026-08-17 13:47 UTCEPSS rescore
  8. 2026-08-16 14:56 UTCEPSS rescore
  9. 2026-08-16 09:55 UTCEG score recompute
  10. 2026-08-16 02:14 UTCEPSS rescore
  11. 2026-08-15 01:30 UTCEPSS rescore
  12. 2026-08-14 06:14 UTCEG score recompute
  13. 2026-08-13 22:00 UTCEPSS rescore
  14. 2026-08-12 20:33 UTCEG score recompute
  15. 2026-08-12 13:50 UTCEPSS rescore
  16. 2026-08-11 03:53 UTCEG score recompute
  17. 2026-08-11 00:00 UTCEPSS rescore
  18. 2026-08-10 04:51 UTCEG score recompute
  19. 2026-08-09 13:46 UTCEPSS rescore
  20. 2026-08-09 05:48 UTCEG score recompute
  21. 2026-08-07 16:14 UTCEG score recompute
  22. 2026-08-06 13:46 UTCEPSS rescore
  23. 2026-08-06 00:43 UTCEG score recompute
  24. 2026-08-05 19:17 UTCEPSS rescore
  25. 2026-08-04 15:10 UTCEPSS rescore
  26. 2026-08-04 10:38 UTCEPSS rescore
  27. 2026-08-03 23:05 UTCEG score recompute
  28. 2026-08-03 10:36 UTCEPSS rescore
  29. 2026-08-02 15:08 UTCEG score recompute
  30. 2026-08-02 02:27 UTCEPSS rescore
  31. 2026-08-01 04:16 UTCEPSS rescore
  32. 2026-07-30 16:28 UTCEPSS rescore
  33. 2026-07-30 01:30 UTCEPSS rescore
  34. 2026-07-27 14:19 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-33996?
CVE-2026-33996 is a medium vulnerability published on March 27, 2026. LibJWT is a C JSON Web Token Library. Starting in version 3.0.0 and prior to version 3.3.0, the JWK parsing for RSA-PSS did not protect against a NULL value when expecting to parse JSON string values. A specially crafted JWK file could exploit this behavior by using integers in places where the…
When was CVE-2026-33996 disclosed?
CVE-2026-33996 was first published in the National Vulnerability Database on March 27, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-33996 actively exploited?
CVE-2026-33996 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 95.4% of all scored CVEs.
What is the CVSS score of CVE-2026-33996?
CVE-2026-33996 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-33996?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-33996, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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