CVE-2026-6331

HIGHNVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory (severity: LOW) published 2026-06-26. NVD baseline CVSS 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this week
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

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

HMAC zero-length tag forgery in EVP_DigestVerifyFinal, where a zero-length tag could be accepted as valid during HMAC verification. In the OpenSSL-compatibility HMAC verify path the supplied signature length was only checked as not exceeding the MAC length, so a zero-length or otherwise truncated tag could pass verification. The fix requires the supplied tag length to exactly equal the MAC length and rejects a zero-length MAC, so a forged short or empty tag is no longer accepted.

CVSS v3
7.5
EG Score
7.5(high)
EPSS
4.4%
KEV
Not listed

Published

June 25, 2026

Last Modified

June 27, 2026

Advisory Details (2)

Auto-updated Jun 27, 2026
Patch available. Sources: github_pr.
generic Patch Available

wolfSSL Security Vulnerabilities | Documentation - wolfSSL

https://www.wolfssl.com/docs/security-vulnerabilities/
github_pr

Various fixes

Fix merged in wolfSSL/wolfssl PR #10192 on 2026-04-15 — awaiting tagged release

https://github.com/wolfSSL/wolfssl/pull/10192

Vendor Advisories for CVE-2026-6331(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 36× in last 7d / 49× 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. 2026-07-06 22:33 UTCEG score recompute
  2. 2026-07-06 22:33 UTCGHSA enrichment
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 09:47 UTCEG score recompute
  6. 2026-07-06 09:47 UTCGHSA enrichment
  7. 2026-07-06 02:23 UTCEPSS rescore
  8. 2026-07-06 02:23 UTCEPSS rescore
  9. 2026-07-05 20:53 UTCEG score recompute
  10. 2026-07-05 20:53 UTCGHSA enrichment
  11. 2026-07-05 08:05 UTCEG score recompute
  12. 2026-07-05 08:05 UTCGHSA enrichment
  13. 2026-07-05 02:31 UTCEPSS rescore
  14. 2026-07-05 02:30 UTCEPSS rescore
  15. 2026-07-04 19:18 UTCEG score recompute
  16. 2026-07-04 19:17 UTCGHSA enrichment
  17. 2026-07-04 06:31 UTCEPSS rescore
  18. 2026-07-04 06:31 UTCEPSS rescore
  19. 2026-07-04 06:30 UTCEG score recompute
  20. 2026-07-04 06:30 UTCGHSA enrichment
  21. 2026-07-03 17:44 UTCEG score recompute
  22. 2026-07-03 17:43 UTCGHSA enrichment
  23. 2026-07-03 04:58 UTCEG score recompute
  24. 2026-07-03 04:58 UTCGHSA enrichment
  25. 2026-07-02 16:12 UTCEG score recompute
Show 24 more
  1. 2026-07-02 16:12 UTCGHSA enrichment
  2. 2026-07-02 03:26 UTCEG score recompute
  3. 2026-07-02 03:26 UTCGHSA enrichment
  4. 2026-07-01 15:07 UTCEPSS rescore
  5. 2026-07-01 14:40 UTCEG score recompute
  6. 2026-07-01 14:40 UTCGHSA enrichment
  7. 2026-07-01 01:54 UTCEG score recompute
  8. 2026-07-01 01:54 UTCGHSA enrichment
  9. 2026-06-30 23:22 UTCEPSS rescore
  10. 2026-06-30 13:08 UTCEG score recompute
  11. 2026-06-30 13:08 UTCGHSA enrichment
  12. 2026-06-30 00:21 UTCEG score recompute
  13. 2026-06-30 00:21 UTCGHSA enrichment
  14. 2026-06-29 14:06 UTCEPSS rescore
  15. 2026-06-29 11:36 UTCEG score recompute
  16. 2026-06-29 11:36 UTCGHSA enrichment
  17. 2026-06-28 22:50 UTCEG score recompute▲ 5.40
  18. 2026-06-28 22:50 UTCGHSA enrichment
  19. 2026-06-28 14:07 UTCEPSS rescore
  20. 2026-06-28 04:56 UTCEPSS rescore
  21. 2026-06-27 21:42 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  22. 2026-06-27 03:08 UTCEPSS rescore
  23. 2026-06-25 23:51 UTCEG score recompute
  24. 2026-06-25 23:50 UTCNVD updatefirst tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-6331?
CVE-2026-6331 is a high vulnerability published on June 25, 2026. HMAC zero-length tag forgery in EVP_DigestVerifyFinal, where a zero-length tag could be accepted as valid during HMAC verification. In the OpenSSL-compatibility HMAC verify path the supplied signature length was only checked as not exceeding the MAC length, so a zero-length or otherwise truncated…
When was CVE-2026-6331 disclosed?
CVE-2026-6331 was first published in the National Vulnerability Database on June 25, 2026, with the most recent update on June 27, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-6331 actively exploited?
CVE-2026-6331 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 4.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-6331?
CVE-2026-6331 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-6331?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-6331, 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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