Authentication Bypass in OPKSSH
Priority MEDIUM 48CWE-305Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-347.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0034 27th percentileScored 2026-11-07
Fix Fixed github.com/openpubkey/opkssh (Go): 0.5.0
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| OPKSSH | OPKSSH | 0.1.0 – 0.4.0 | — | No fix listed | CNA |
| — | github.com/openpubkey/opkssh (Go) | before 0.5.0 | 0.5.0 | Patch available | GHSA-56wx-66px-9j66 |
- OPKSSH VendorOPKSSH Affected 0.1.0 – 0.4.0 Fixed in — No fix listed CNA
- github.com/openpubkey/opkssh (Go) Vendor— Affected before 0.5.0 Fixed in 0.5.0 Patch available GHSA-56wx-66px-9j66
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:openpubkey:openpubkey:*:*:*:*:*:*:*:* | before 0.10.0 | Vulnerable | Openpubkey |
| cpe:2.3:a:openpubkey:opkssh:*:*:*:*:*:*:*:* | before 0.5.0 | Vulnerable | Openpubkey |
- cpe:2.3:a:openpubkey:openpubkey:*:*:*:*:*:*:*:* Versions before 0.10.0 Vulnerable ·Openpubkey
- cpe:2.3:a:openpubkey:opkssh:*:*:*:*:*:*:*:* Versions before 0.5.0 Vulnerable ·Openpubkey
Remediation
- Fix · GHSA-56wx-66px-9j66 github.com/openpubkey/opkssh (Go) Fixed in 0.5.0 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-4658
- 2026-10-03 Alias added: GHSA-56wx-66px-9j66
References
More Openpubkey vulnerabilities
- TI-2025-03309 Authentication Bypass in OpenPubKey CVSS 4.0CRITICAL 9.3
Sources
- CVE-2025-4658 · CVE Program
- CVE-2025-4658 · NVD
- FIRST EPSS
- GHSA-56wx-66px-9j66 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences