CVE-2026-44375

Description

Nerdbank.MessagePack is a NativeAOT-compatible MessagePack serialization library. Prior to 1.1.62, Nerdbank.MessagePack contains an uncontrolled stack allocation vulnerability in DateTime decoding. A malicious MessagePack payload can declare an oversized timestamp extension length, causing the reader to allocate an attacker-controlled number of bytes on the stack. This can trigger a StackOverflowException, which is not catchable by user code and terminates the process. This vulnerability is fixed in 1.1.62.

References

• https://github.com/AArnott/Nerdbank.MessagePack/commit/7d1eb319cfabe7280e70699946c9a48579fa2f30
• https://github.com/AArnott/Nerdbank.MessagePack/pull/941
• https://github.com/AArnott/Nerdbank.MessagePack/releases/tag/v1.1.62
• https://github.com/AArnott/Nerdbank.MessagePack/security/advisories/GHSA-2cwq-pwfr-wcw3