CVE-2025-4658: opkssh Signature Bypass (CVSS 9.8)

Description

Versions of OpenPubkey library prior to 0.10.0 contained a vulnerability that would allow a specially crafted JWS to bypass signature verification. As OPKSSH depends on the OpenPubkey library for authentication, this vulnerability in OpenPubkey also applies to OPKSSH versions prior to 0.5.0 and would allow an attacker to bypass OPKSSH authentication.

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CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-305 CWE-305

CWE-347 CWE-347

Affected Products

Vendor	Product	Versions
openpubkey	openpubkey	< 0.10.0
openpubkey	opkssh	< 0.5.0

References

Other References

https://github.com/openpubkey/opkssh

Frequently Asked Questions

What is CVE-2025-4658? +

Versions of OpenPubkey library prior to 0.10.0 contained a vulnerability that would allow a specially crafted JWS to bypass signature verification. As OPKSSH depends on the OpenPubkey library for authentication, this vulnerability in OpenPubkey also applies to OPKSSH versions prior to 0.5.0 and would allow an attacker to bypass OPKSSH authentication. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2025-4658? +

CVE-2025-4658 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2025-4658? +

CVE-2025-4658 affects products from openpubkey, specifically: openpubkey, opkssh. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-4658? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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