CVE-2026-35387: CWE-670 Always-Incorrect Control Flow Implementation in OpenBSD OpenSSH
OpenSSH versions before 10.3 have a vulnerability where specifying any ECDSA algorithm in PubkeyAcceptedAlgorithms or HostbasedAcceptedAlgorithms causes all ECDSA algorithms to be accepted. This is due to incorrect control flow implementation. The issue is classified under CWE-670 and has a low CVSS score of 3.1.
AI Analysis
Technical Summary
CVE-2026-35387 describes a control flow implementation flaw in OpenSSH prior to version 10.3. When any ECDSA algorithm is listed in the PubkeyAcceptedAlgorithms or HostbasedAcceptedAlgorithms configuration options, the software misinterprets this to mean that all ECDSA algorithms are accepted. This behavior deviates from the intended selective acceptance of algorithms and may lead to unintended algorithm usage during authentication.
Potential Impact
The vulnerability does not directly compromise confidentiality or availability but may lead to the use of unintended ECDSA algorithms for authentication, potentially weakening the security posture. The CVSS score of 3.1 reflects a low severity with limited impact, specifically a low integrity impact and no confidentiality or availability impact.
Mitigation Recommendations
No official patch or fix information is provided in the available data. Patch status is not yet confirmed — check the OpenBSD vendor advisory for current remediation guidance. Until a fix is available, administrators should review and carefully configure ECDSA algorithm settings to avoid unintended acceptance. Monitoring vendor communications for updates is recommended.
CVE-2026-35387: CWE-670 Always-Incorrect Control Flow Implementation in OpenBSD OpenSSH
Description
OpenSSH versions before 10.3 have a vulnerability where specifying any ECDSA algorithm in PubkeyAcceptedAlgorithms or HostbasedAcceptedAlgorithms causes all ECDSA algorithms to be accepted. This is due to incorrect control flow implementation. The issue is classified under CWE-670 and has a low CVSS score of 3.1.
CVSS v3.1
Score 3.1low
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-35387 describes a control flow implementation flaw in OpenSSH prior to version 10.3. When any ECDSA algorithm is listed in the PubkeyAcceptedAlgorithms or HostbasedAcceptedAlgorithms configuration options, the software misinterprets this to mean that all ECDSA algorithms are accepted. This behavior deviates from the intended selective acceptance of algorithms and may lead to unintended algorithm usage during authentication.
Potential Impact
The vulnerability does not directly compromise confidentiality or availability but may lead to the use of unintended ECDSA algorithms for authentication, potentially weakening the security posture. The CVSS score of 3.1 reflects a low severity with limited impact, specifically a low integrity impact and no confidentiality or availability impact.
Mitigation Recommendations
No official patch or fix information is provided in the available data. Patch status is not yet confirmed — check the OpenBSD vendor advisory for current remediation guidance. Until a fix is available, administrators should review and carefully configure ECDSA algorithm settings to avoid unintended acceptance. Monitoring vendor communications for updates is recommended.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-04-02T16:52:52.884Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69cea282e6bfc5ba1ded3a5c
Added to database: 04/02/2026, 17:08:18 UTC
Last enriched: 06/24/2026, 17:21:33 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 108
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