Summary
rust-openssl has incorrect bounds assertion in aes key wrap
aes::unwrap_key() has an incorrect bounds assertion on the out buffer size, which can lead to out-of-bounds write.
Details
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.
Impact
Vulnerable applications using AES keywrap and allowing attacker controlled buffer sizes could have an attacker trigger an out-of-bounds write.
A write operation targets a memory location beyond the intended buffer boundary. Typical impact: memory corruption, crash, or arbitrary code execution.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2026-41678? CVE-2026-41678 is a high-severity out-of-bounds write vulnerability in openssl (rust), affecting versions >= 0.10.24, < 0.10.78. It is fixed in 0.10.78. A write operation targets a memory location beyond the intended buffer boundary.
- Which versions of openssl are affected by CVE-2026-41678? openssl (rust) versions >= 0.10.24, < 0.10.78 is affected.
- Is there a fix for CVE-2026-41678? Yes. CVE-2026-41678 is fixed in 0.10.78. Upgrade to this version or later.
- Is CVE-2026-41678 exploitable, and should I be worried? Whether CVE-2026-41678 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-41678 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-41678? Upgrade
opensslto 0.10.78 or later.