CVE-2026-93994 (GCVE-0-2026-93994)
Vulnerability from cvelistv5 – Published: 2026-09-30 09:45 – Updated: 2026-09-30 14:29
VLAI
EPSS
VEX
Title
Apache MINA SSHD: Repeated-publickey policy bypass on server
Summary
Apache MINA SSHD is a Java library for client-side and server-side SSH. SSH servers can be configured to require multi-authentication schemes, for instance two different public keys, not just one. In OpenSSH, this would be done by setting in sshd_config AuthenticationMethods "publickey,publickey". Apache MINA SSHD provides an equivalent configuration mechanism.
In Apache MINA SSHD versions up to 2.19.0 and 3.0.0-M1 to 3.0.0-M5 the server code in component sshd-core does not enforce that the two public keys presented are different. A user can thus successfully authenticate with only one of the two key pairs required by presenting this single key twice. This is a partial authentication bypass.
Users are recommended to upgrade to version 2.20.0 or 3.0.0-M6, which fix this issue.
Severity
8.1 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-30 14:29 UTC
CWE
- CWE-304 - Missing critical step in authentication
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://lists.apache.org/thread.html/9t3vsm8rnvwd… | vendor-advisory |
| http://www.openwall.com/lists/oss-security/2026/0… |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Apache Software Foundation | Apache MINA SSHD |
Affected:
0 , < 2.20.0
(maven)
Affected: 3.0.0-M1 , < 3.0.0-M6 (maven) |
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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