CVE-2026-41681 | rust-openssl: MdCtxRef::digest_final() writes past caller buffer with no length check

rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.10.39 to before 0.10.78, EVP_DigestFinal() always writes EVP_MD_CTX_size(ctx) to the out buffer. If out is smaller than that, MdCtxRef::digest_final() writes past its end, usually corrupting the stack. This is reachable from safe Rust. This vulnerability is fixed in 0.10.78.

Published: 2026-04-24 Last update: 2026-04-27 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-41681 is rated Low Risk (38.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-41681

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-30 0.04% 0.06% +0.01%
2 2026-04-25 0.04%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-41681

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 4.0 HIGH
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:H)
High confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:H)
High availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:U)
Unreported: no public PoC, no reported exploitation, and no known simplification tools.
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
[email protected]

Weakness enumeration for CVE-2026-41681

GitHub Security Advisory for CVE-2026-41681

GHSA-ghm9-cr32-g9qj · Severity: high · Ecosystem: rust — rust-openssl: rustMdCtxRef::digest_final() writes past caller buffer with no length check

OS Trackers for CVE-2026-41681

vendor priority summary link
debian not yet assigned CVE-2026-41681 not yet assigned priority: Debian including 1 source packages (rust-openssl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-41681
ubuntu medium CVE-2026-41681 medium priority: Ubuntu including 1 source packages (rust-openssl), 6 status rows across 6 suites (focal, jammy, noble, questing, resolute, upstream): needed 3, not-affected 2, released 1. https://ubuntu.com/security/CVE-2026-41681

Affected software / configurations for CVE-2026-41681

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-41681

cvelogic Threat Intelligence