CVE-2026-41678

CVE-2026-41678 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-787.

Key facts

Description

rust-openssl provides OpenSSL bindings for the Rust programming language. From to before 0.10.78, aes::unwrap_key() contains an incorrect assertion: it checks that out.len() + 8 <= in_.len(), but this condition is reversed. The intended invariant is out.len() >= in_.len() - 8, ensuring the output buffer is large enough. Because of the inverted check, the function only accepts buffers at or below the minimum required size and rejects larger ones. If a smaller buffer is provided the function will write past the end of out by in_.len() - 8 - out.len() bytes, causing an out-of-bounds write from a safe public function. This vulnerability is fixed in 0.10.78.

Frequently asked questions

What is CVE-2026-41678?
rust-openssl provides OpenSSL bindings for the Rust programming language. From to before 0.10.78, aes::unwrap_key() contains an incorrect assertion: it checks that out.len() + 8 <= in_.len(), but this condition is reversed. The intended invariant is out.len() >= in_.len() - 8, ensuring the output buffer is large enough. Because of the inverted check, the function only accepts buffers at or below the minimum required size and rejects larger ones. If a smaller buffer is provided the function will write past the end of out by in_.len() - 8 - out.len() bytes, causing an out-of-bounds write from a safe public function. This vulnerability is fixed in 0.10.78.
How severe is CVE-2026-41678?
CVE-2026-41678 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-2026-41678 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-41678?
CVE-2026-41678 affects Rust-openssl Project Rust-openssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-41678?
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-2026-41678 have an EU (EUVD) identifier?
Yes. CVE-2026-41678 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25584.
When was CVE-2026-41678 published?
CVE-2026-41678 was published on 2026-04-24 and last updated on 2026-06-17.

References

Affected products (1)

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