How severe is CVE-2026-41676?

CVE-2026-41676 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-41676 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-41676?

CVE-2026-41676 affects Rust-openssl Project Rust-openssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-41676?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2026-41676 have an EU (EUVD) identifier?

Yes. CVE-2026-41676 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25582.

When was CVE-2026-41676 published?

CVE-2026-41676 was published on 2026-04-24 and last updated on 2026-06-17.

CVE-2026-41676

CVE-2026-41676 is a critical-severity vulnerability in Rust-openssl Project Rust-openssl with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-131.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 7.2
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-25582
Weakness: CWE-131
Affected product: Rust-openssl Project Rust-openssl
Published: 2026-04-24
Last modified: 2026-06-17

Description

rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.27 to before 0.10.78, Deriver::derive (and PkeyCtxRef::derive) sets len = buf.len() and passes it as the in/out length to EVP_PKEY_derive, relying on OpenSSL to honor it. On OpenSSL 1.1.x, X25519, X448, DH and HKDF-extract ignore the incoming *keylen, unconditionally writing the full shared secret (32/56/prime-size bytes). A caller passing a short slice gets a heap/stack overflow from safe code. OpenSSL 3.x providers do check, so this only impacts older OpenSSL. This vulnerability is fixed in 0.10.78.

Frequently asked questions

What is CVE-2026-41676?: rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.27 to before 0.10.78, Deriver::derive (and PkeyCtxRef::derive) sets len = buf.len() and passes it as the in/out length to EVP_PKEY_derive, relying on OpenSSL to honor it. On OpenSSL 1.1.x, X25519, X448, DH and HKDF-extract ignore the incoming *keylen, unconditionally writing the full shared secret (32/56/prime-size bytes). A caller passing a short slice gets a heap/stack overflow from safe code. OpenSSL 3.x providers do check, so this only impacts older OpenSSL. This vulnerability is fixed in 0.10.78.
How severe is CVE-2026-41676?: CVE-2026-41676 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-41676 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-41676?: CVE-2026-41676 affects Rust-openssl Project Rust-openssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-41676?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-41676 have an EU (EUVD) identifier?: Yes. CVE-2026-41676 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25582.
When was CVE-2026-41676 published?: CVE-2026-41676 was published on 2026-04-24 and last updated on 2026-06-17.

References

https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-pqf5-4pqq-29f5

Affected products (1)

cpe:2.3:a:rust-openssl_project:rust-openssl:*:*:*:*:*:rust:*:*

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