CVE-2026-8720

HIGHNVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory 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.

wc_Blake2bHmacFinal and wc_Blake2sHmacFinal discard the message when the key length exceeds the block size, producing a MAC that is independent of the input. When the supplied key is longer than the BLAKE2 block size the key-hashing branch reinitialized the running hash state, discarding the accumulated message data, so the resulting MAC depended only on the key and not on the message being authenticated. This bug is specific to the HMAC-BLAKE2 APIs that were added in wolfSSL version 5.9.0.

CVSS v3
7.5
EG Score
7.5(high)
EPSS
1.6%
KEV
Not listed

Published

June 25, 2026

Last Modified

June 27, 2026

Advisory Details (2)

Auto-updated Jun 25, 2026
Patch available. Sources: github_pr.
generic Patch Available

wolfSSL Security Vulnerabilities | Documentation - wolfSSL

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

Fix Blake2 oversized key path

Fix merged in wolfSSL/wolfssl PR #10447 on 2026-05-12 — awaiting tagged release

https://github.com/wolfSSL/wolfssl/pull/10447

Vendor Advisories for CVE-2026-8720(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 38× in last 7d / 57× 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. 2026-07-07 02:29 UTCEG score recompute
  2. 2026-07-07 02:29 UTCGHSA enrichment
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 14:29 UTCEG score recompute
  6. 2026-07-06 14:29 UTCGHSA enrichment
  7. 2026-07-06 02:30 UTCEG score recompute
  8. 2026-07-06 02:30 UTCGHSA enrichment
  9. 2026-07-06 02:23 UTCEPSS rescore
  10. 2026-07-06 02:23 UTCEPSS rescore
  11. 2026-07-05 14:30 UTCEG score recompute
  12. 2026-07-05 14:30 UTCGHSA enrichment
  13. 2026-07-05 02:31 UTCEPSS rescore
  14. 2026-07-05 02:30 UTCEPSS rescore
  15. 2026-07-05 02:30 UTCEG score recompute
  16. 2026-07-05 02:30 UTCGHSA enrichment
  17. 2026-07-04 14:30 UTCEG score recompute
  18. 2026-07-04 14:30 UTCGHSA enrichment
  19. 2026-07-04 06:31 UTCEPSS rescore
  20. 2026-07-04 06:31 UTCEPSS rescore
  21. 2026-07-04 02:30 UTCEG score recompute
  22. 2026-07-04 02:30 UTCGHSA enrichment
  23. 2026-07-03 14:25 UTCEG score recompute
  24. 2026-07-03 14:25 UTCGHSA enrichment
  25. 2026-07-03 02:25 UTCEG score recompute
Show 32 more
  1. 2026-07-03 02:25 UTCGHSA enrichment
  2. 2026-07-02 14:25 UTCEG score recompute
  3. 2026-07-02 14:25 UTCGHSA enrichment
  4. 2026-07-02 02:25 UTCEG score recompute
  5. 2026-07-02 02:25 UTCGHSA enrichment
  6. 2026-07-01 15:07 UTCEPSS rescore
  7. 2026-07-01 14:23 UTCEG score recompute
  8. 2026-07-01 14:23 UTCGHSA enrichment
  9. 2026-07-01 02:24 UTCEG score recompute
  10. 2026-07-01 02:24 UTCGHSA enrichment
  11. 2026-06-30 23:22 UTCEPSS rescore
  12. 2026-06-30 14:24 UTCEG score recompute
  13. 2026-06-30 14:24 UTCGHSA enrichment
  14. 2026-06-30 02:22 UTCEG score recompute
  15. 2026-06-30 02:22 UTCGHSA enrichment
  16. 2026-06-29 14:22 UTCEG score recompute
  17. 2026-06-29 14:22 UTCGHSA enrichment
  18. 2026-06-29 14:06 UTCEPSS rescore
  19. 2026-06-29 02:23 UTCEG score recompute
  20. 2026-06-29 02:23 UTCGHSA enrichment
  21. 2026-06-28 14:23 UTCEG score recompute
  22. 2026-06-28 14:23 UTCGHSA enrichment
  23. 2026-06-28 14:07 UTCEPSS rescore
  24. 2026-06-28 04:56 UTCEPSS rescore
  25. 2026-06-28 02:23 UTCEG score recompute▲ 1.60
  26. 2026-06-28 02:23 UTCGHSA enrichment
  27. 2026-06-27 19:44 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  28. 2026-06-27 03:08 UTCEPSS rescore
  29. 2026-06-27 01:07 UTCEG score recompute
  30. 2026-06-27 01:07 UTCGHSA enrichment
  31. 2026-06-25 23:51 UTCEG score recompute
  32. 2026-06-25 23:50 UTCNVD updatefirst tracked

Frequently asked(5)

What is CVE-2026-8720?
CVE-2026-8720 is a high vulnerability published on June 25, 2026. wcBlake2bHmacFinal and wcBlake2sHmacFinal discard the message when the key length exceeds the block size, producing a MAC that is independent of the input. When the supplied key is longer than the BLAKE2 block size the key-hashing branch reinitialized the running hash state, discarding the…
When was CVE-2026-8720 disclosed?
CVE-2026-8720 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-2026-8720 actively exploited?
CVE-2026-8720 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-8720?
CVE-2026-8720 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-8720?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-8720, 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

Explore the affected products and dependency analysis for CVE-2026-8720

Explore →

Is Your Infrastructure Affected by CVE-2026-8720?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs