What’s Vulnerable › Vulnerabilities

CVE-2024-45402: Picotls double free

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2024-10-11 · updated 2026-06-17
• Weakness: CWE-415

Description

Picotls is a TLS protocol library that allows users select different crypto backends based on their use case. When parsing a spoofed TLS handshake message, picotls (specifically, bindings within picotls that call the crypto libraries) may attempt to free the same memory twice. This double free occurs during the disposal of multiple objects without any intervening calls to malloc Typically, this triggers the malloc implementation to detect the error and abort the process. However, depending on the internals of malloc and the crypto backend being used, the flaw could potentially lead to a use-after-free scenario, which might allow for arbitrary code execution. The vulnerability is addressed with commit 9b88159ce763d680e4a13b6e8f3171ae923a535d.

Affected products

• h2o picotls: from 2024-08-12 before 2024-10-10 — fixed in 2024-10-10

How to fix

Upgrade to a fixed version: h2o picotls 2024-10-10. Check the vendor advisory for mitigations.

References

• https://github.com/h2o/picotls/commit/9b88159ce763d680e4a13b6e8f3171ae923a535d
• https://github.com/h2o/picotls/security/advisories/GHSA-w7c8-wjx9-vvvv

Get alerted when CVE-2024-45402 or the next vulnerability affects your stack