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
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)
EG Risk
—
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 10× in last 7d / 71× 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. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:25 UTCEPSS rescore
  3. 2026-07-21 15:25 UTCEPSS rescore
  4. 2026-07-20 17:08 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-18 10:04 UTCEPSS rescore
  7. 2026-07-17 05:37 UTCGHSA enrichment
  8. 2026-07-16 17:38 UTCGHSA enrichment
  9. 2026-07-16 17:03 UTCEPSS rescore
  10. 2026-07-16 05:38 UTCGHSA enrichment
  11. 2026-07-15 17:37 UTCGHSA enrichment
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-15 05:19 UTCGHSA enrichment
  14. 2026-07-14 16:51 UTCGHSA enrichment
  15. 2026-07-14 04:50 UTCGHSA enrichment
  16. 2026-07-13 22:31 UTCEPSS rescore
  17. 2026-07-13 16:46 UTCGHSA enrichment
  18. 2026-07-13 06:13 UTCEPSS rescore
  19. 2026-07-13 04:45 UTCGHSA enrichment
  20. 2026-07-12 16:43 UTCGHSA enrichment
  21. 2026-07-12 04:43 UTCGHSA enrichment
  22. 2026-07-11 16:43 UTCGHSA enrichment
  23. 2026-07-11 04:43 UTCGHSA enrichment
  24. 2026-07-10 16:43 UTCGHSA enrichment
  25. 2026-07-10 04:43 UTCGHSA enrichment
Show 46 more
  1. 2026-07-09 19:10 UTCEPSS rescore
  2. 2026-07-09 16:38 UTCGHSA enrichment
  3. 2026-07-09 04:32 UTCGHSA enrichment
  4. 2026-07-08 16:33 UTCGHSA enrichment
  5. 2026-07-08 15:16 UTCEPSS rescore
  6. 2026-07-08 04:32 UTCGHSA enrichment
  7. 2026-07-07 16:13 UTCGHSA enrichment
  8. 2026-07-07 13:46 UTCEPSS rescore
  9. 2026-07-07 02:29 UTCGHSA enrichment
  10. 2026-07-06 16:27 UTCEPSS rescore
  11. 2026-07-06 16:27 UTCEPSS rescore
  12. 2026-07-06 14:29 UTCGHSA enrichment
  13. 2026-07-06 02:30 UTCGHSA enrichment
  14. 2026-07-06 02:23 UTCEPSS rescore
  15. 2026-07-06 02:23 UTCEPSS rescore
  16. 2026-07-05 14:30 UTCGHSA enrichment
  17. 2026-07-05 02:31 UTCEPSS rescore
  18. 2026-07-05 02:30 UTCEPSS rescore
  19. 2026-07-05 02:30 UTCGHSA enrichment
  20. 2026-07-04 14:30 UTCGHSA enrichment
  21. 2026-07-04 06:31 UTCEPSS rescore
  22. 2026-07-04 06:31 UTCEPSS rescore
  23. 2026-07-04 02:30 UTCGHSA enrichment
  24. 2026-07-03 14:25 UTCGHSA enrichment
  25. 2026-07-03 02:25 UTCGHSA enrichment
  26. 2026-07-02 14:25 UTCGHSA enrichment
  27. 2026-07-02 02:25 UTCGHSA enrichment
  28. 2026-07-01 15:07 UTCEPSS rescore
  29. 2026-07-01 14:23 UTCGHSA enrichment
  30. 2026-07-01 02:24 UTCGHSA enrichment
  31. 2026-06-30 23:22 UTCEPSS rescore
  32. 2026-06-30 14:24 UTCGHSA enrichment
  33. 2026-06-30 02:22 UTCGHSA enrichment
  34. 2026-06-29 14:22 UTCGHSA enrichment
  35. 2026-06-29 14:06 UTCEPSS rescore
  36. 2026-06-29 02:23 UTCGHSA enrichment
  37. 2026-06-28 14:23 UTCGHSA enrichment
  38. 2026-06-28 14:07 UTCEPSS rescore
  39. 2026-06-28 04:56 UTCEPSS rescore
  40. 2026-06-28 02:23 UTCEG score recompute▲ 1.60
  41. 2026-06-28 02:23 UTCGHSA enrichment
  42. 2026-06-27 19:44 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  43. 2026-06-27 03:08 UTCEPSS rescore
  44. 2026-06-27 01:07 UTCGHSA enrichment
  45. 2026-06-25 23:51 UTCEG score recompute
  46. 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

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