CVE-2026-41898 — rust-openssl: Unchecked callback length in...

HIGH

rust-openssl: Unchecked callback length in PSK/cookie trampolines leaks adjacent memory to peer

Published April 22, 2026Updated September 10, 2026Source: osv

Summary

The FFI trampolines behind `SslContextBuilder::set_psk_client_callback`, `set_psk_server_callback`, `set_cookie_generate_cb`, and `set_stateless_cookie_generate_cb` forwarded the user closure's returned usize directly to OpenSSL without checking it against the `&mut [u8]` that was handed to the closure. This can lead to buffer overflows and other unintended consequences.

Advisory Timeline

First published April 22, 2026 (173 days ago).
Last revised September 10, 2026 — 140 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

Cargo

Update openssl to 0.10.78 or later

cargo update -p openssl --precise 0.10.78

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (1)

Affects 1 ecosystem: crates.io (1).

Package	Ecosystem	Affected	Fixed In
openssl	crates.io	All versions	0.10.78

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-126
View on MITRE
CWE-130
View on MITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 7.6 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

—

Confidentiality

—

Integrity

—

Availability

—

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N

References

Frequently Asked Questions

What is CVE-2026-41898?: rust-openssl: Unchecked callback length in PSK/cookie trampolines leaks adjacent memory to peer This vulnerability has been assigned a severity rating of HIGH (CVSS score: 7.6/10).
How do I check if my project is affected by CVE-2026-41898?: CVE-2026-41898 affects openssl. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2026-41898 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

7.6

High exploitability or significant impact. Prioritize remediation within days.

Also Known As

GHSA-hppc-g8h3-xhp3

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