CVE-2026-59993 (GCVE-0-2026-59993)

Vulnerability from cvelistv5 – Published: 2026-10-30 21:01 – Updated: 2026-10-30 21:01
VLAI
Title
Picotls has NULL pointer dereference during handshake, when running as a client
Summary
Picotls is a TLS protocol library that allows users select different crypto backends based on their use case. In affected revisions through 44bc503, when picotls is used as a `client-side TLS stack`, a peer can send a `HelloRetryRequest` followed by a `spoofed Hello message` that causes a null-pointer dereference. This can terminate the consuming process, including a process performing other work, resulting in denial of service. This issue is fixed in commit a06ca41.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8129 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
h2o picotls Affected: < a06ca417a16f9126808bf5cabe6c5e6e0f16ecae
guessed Create a notification for this product.
Show details on NVD website
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    "dateReserved": "2026-07-07T19:41:00.005Z",
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        ],
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        "lastModified": "2026-10-30T21:17:13.193",
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}



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