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CVE-2026-35388 (GCVE-0-2026-35388)

Vulnerability from cvelistv5 – Published: 2026-04-02 16:57 – Updated: 2026-04-02 18:16
VLAI
Summary
OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing sessions.
Severity
2.5 (Low)
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-02 17:46 UTC
CWE
  • CWE-420 - Unprotected Alternate Channel
Assigner
References
Impacted products
Vendor Product Version CPE status
OpenBSD OpenSSH Affected: 0 , < 10.3 (custom)
    cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*
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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

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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.


Detection rules are retrieved from Rulezet.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.