CVE-2026-55958

HIGHNVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-06-25. 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.

Out-of-bounds write in the Renesas TSIP TLS 1.3 transcript buffer. In tsip_StoreMessage() the capacity check guarding the fixed message bag (MSGBAG_SIZE) sets an error code but fails to return, so execution falls through to an XMEMCPY that writes past the end of the buffer once the accumulated TLS 1.3 handshake transcript exceeds MSGBAG_SIZE (8 KB), corrupting adjacent heap state and potentially causing a remote denial of service crash. The bag is sized to hold a normal handshake, so this is reached only by an unusually large but valid certificate chain, or by a malicious or man-in-the-middle server sending an oversized handshake message to a client that does not strictly verify the chain. This only affects builds using the Renesas TSIP TLS port (WOLFSSL_RENESAS_TSIP_TLS) as a TLS 1.3 client on Renesas MCUs with TSIP hardware enabled, and is rated High within those builds. All other configurations are unaffected.

CVSS v3
7.5
EG Score
7.5(high)
EPSS
18.5%
KEV
Not listed

Published

June 25, 2026

Last Modified

June 26, 2026

Advisory Details (2)

Auto-updated Jun 26, 2026
Patch available. Sources: github_pr.
generic Patch Available

wolfSSL Security Vulnerabilities | Documentation - wolfSSL

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

Renesas TSIP: skip XMEMCPY on MEMORY_E from tsip_StoreMessage()

Fix merged in wolfSSL/wolfssl PR #10705 on 2026-06-16 — awaiting tagged release

https://github.com/wolfSSL/wolfssl/pull/10705

Vendor Advisories for CVE-2026-55958(2)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 36× in last 7d / 60× 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 18:19 UTCEG score recompute
  2. 2026-07-06 18:19 UTCGHSA enrichment
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 05:33 UTCEG score recompute
  6. 2026-07-06 05:33 UTCGHSA enrichment
  7. 2026-07-06 02:23 UTCEPSS rescore
  8. 2026-07-06 02:23 UTCEPSS rescore
  9. 2026-07-05 16:47 UTCEG score recompute
  10. 2026-07-05 16:47 UTCGHSA enrichment
  11. 2026-07-05 03:59 UTCEG score recompute
  12. 2026-07-05 03:59 UTCGHSA enrichment
  13. 2026-07-05 02:31 UTCEPSS rescore
  14. 2026-07-05 02:30 UTCEPSS rescore
  15. 2026-07-04 15:14 UTCEG score recompute
  16. 2026-07-04 15:14 UTCGHSA enrichment
  17. 2026-07-04 06:31 UTCEPSS rescore
  18. 2026-07-04 06:31 UTCEPSS rescore
  19. 2026-07-04 02:25 UTCEG score recompute
  20. 2026-07-04 02:25 UTCGHSA enrichment
  21. 2026-07-03 13:38 UTCEG score recompute
  22. 2026-07-03 13:38 UTCGHSA enrichment
  23. 2026-07-03 00:53 UTCEG score recompute
  24. 2026-07-03 00:53 UTCGHSA enrichment
  25. 2026-07-02 12:07 UTCEG score recompute
Show 35 more
  1. 2026-07-02 12:07 UTCGHSA enrichment
  2. 2026-07-01 23:20 UTCEG score recompute
  3. 2026-07-01 23:19 UTCGHSA enrichment
  4. 2026-07-01 15:07 UTCEPSS rescore
  5. 2026-07-01 10:34 UTCEG score recompute
  6. 2026-07-01 10:34 UTCGHSA enrichment
  7. 2026-06-30 23:22 UTCEPSS rescore
  8. 2026-06-30 21:48 UTCEG score recompute
  9. 2026-06-30 21:48 UTCGHSA enrichment
  10. 2026-06-30 09:02 UTCEG score recompute
  11. 2026-06-30 09:02 UTCGHSA enrichment
  12. 2026-06-29 20:17 UTCEG score recompute
  13. 2026-06-29 20:17 UTCGHSA enrichment
  14. 2026-06-29 14:06 UTCEPSS rescore
  15. 2026-06-29 14:06 UTCEPSS rescore
  16. 2026-06-29 07:31 UTCEG score recompute
  17. 2026-06-29 07:31 UTCGHSA enrichment
  18. 2026-06-28 18:46 UTCEG score recompute
  19. 2026-06-28 18:46 UTCGHSA enrichment
  20. 2026-06-28 14:07 UTCEPSS rescore
  21. 2026-06-28 06:00 UTCEG score recompute
  22. 2026-06-28 06:00 UTCGHSA enrichment
  23. 2026-06-28 04:56 UTCEPSS rescore
  24. 2026-06-28 04:56 UTCEPSS rescore
  25. 2026-06-27 17:15 UTCEG score recompute
  26. 2026-06-27 17:15 UTCGHSA enrichment
  27. 2026-06-27 04:30 UTCEG score recompute▼ 0.80
  28. 2026-06-27 04:29 UTCGHSA enrichment
  29. 2026-06-27 03:08 UTCEPSS rescore
  30. 2026-06-26 19:41 UTCNVD updateCVSS v3 → 7.5
  31. 2026-06-26 15:45 UTCEG score recompute▲ 8.30
  32. 2026-06-26 15:44 UTCGHSA enrichment
  33. 2026-06-26 15:40 UTCNVD updateCVSS v3 → 8.3 · CVSS v4 → 8.3
  34. 2026-06-25 21:46 UTCEG score recompute
  35. 2026-06-25 21:46 UTCGHSA enrichment

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-55958?
CVE-2026-55958 is a high vulnerability published on June 25, 2026. Out-of-bounds write in the Renesas TSIP TLS 1.3 transcript buffer. In tsipStoreMessage() the capacity check guarding the fixed message bag (MSGBAGSIZE) sets an error code but fails to return, so execution falls through to an XMEMCPY that writes past the end of the buffer once the accumulated TLS…
When was CVE-2026-55958 disclosed?
CVE-2026-55958 was first published in the National Vulnerability Database on June 25, 2026, with the most recent update on June 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55958 actively exploited?
CVE-2026-55958 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 18.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-55958?
CVE-2026-55958 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-55958?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55958, 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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