Authentication Bypass Affecting libcurl package, versions [,8.0.0)


Severity

Recommended
0.0
medium
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.05% (16th percentile)

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  • Snyk IDSNYK-CONAN-LIBCURL-10076460
  • published8 May 2025
  • disclosed20 Mar 2023
  • creditUnknown

Introduced: 20 Mar 2023

CVE-2023-27535  (opens in a new tab)
CWE-287  (opens in a new tab)

How to fix?

Upgrade libcurl to version 8.0.0 or higher.

Overview

Affected versions of this package are vulnerable to Authentication Bypass libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. However, several FTP settings were left out from the configuration match checks, making them match too easily. The settings in questions are CURLOPT_FTP_ACCOUNT, CURLOPT_FTP_ALTERNATIVE_TO_USER, CURLOPT_FTP_SSL_CCC and CURLOPT_USE_SSL level.

CVSS Base Scores

version 3.1