CVE-2023-27538 (GCVE-0-2023-27538)

Vulnerability from cvelistv5 – Published: 2023-03-30 00:00 – Updated: 2025-06-09 14:52
VLAI
Summary
An authentication bypass vulnerability exists in libcurl prior to v8.0.0 where it reuses a previously established SSH connection despite the fact that an SSH option was modified, which should have prevented reuse. libcurl maintains a pool of previously used connections to reuse them for subsequent transfers if the configurations match. However, two SSH settings were omitted from the configuration check, allowing them to match easily, potentially leading to the reuse of an inappropriate connection.
Severity
7.7 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-06-09 14:52 UTC
CWE
  • CWE-305 - Authentication Bypass by Primary Weakness (CWE-305)
Assigner
References
Impacted products
Vendor Product Version CPE status
n/a https://github.com/curl/curl Affected: Fixed in 8.0.0
Show details on NVD website
To clipboard 

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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.