CVE-2026-41676 Rust Openssl Project CVE debrief

Who should care

Users of Rust-OpenSSL versions between 0.9.27 and before 0.10.78 should update to version 0.10.78 or later to mitigate this vulnerability. Affected operators include developers and maintainers of systems using Rust-OpenSSL. The vulnerability-management impact includes reviewing and updating affected systems and applications. Security teams should monitor for potential exploitation attempts.

Technical summary

The Deriver::derive and PkeyCtxRef::derive functions in Rust-OpenSSL versions between 0.9.27 and before 0.10.78 set the length of the buffer and pass it to EVP_PKEY_derive, relying on OpenSSL to honor it. However, on OpenSSL 1.1.x, certain functions ignore the incoming key length and write the full shared secret, leading to a potential heap/stack overflow when a short slice is passed. This vulnerability is fixed in version 0.10.78. Affected product context includes users of Rust-OpenSSL versions between 0.9.27 and before 0.10.78.

Defensive priority

High

Recommended defensive actions

• Update Rust-OpenSSL to version 0.10.78 or later
• Review and update affected systems and applications
• Monitor for potential exploitation attempts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD detail provide information on the vulnerability and its impact. The vendor advisory provides mitigation and remediation guidance. Users should verify the affected versions of Rust-OpenSSL and review system deployments. Evidence is limited to public sources and may not cover all affected systems or potential variants. Defenders should check for updates and monitor for potential exploitation attempts.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.