Improper Certificate Validation Affecting libcurl package, versions [7.76.0,8.1.1)


Severity

Recommended
0.0
medium
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.3% (53rd percentile)

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  • Snyk IDSNYK-CONAN-LIBCURL-10076465
  • published8 May 2025
  • disclosed17 May 2023
  • creditDaniel Stenberg, Hiroki Kurosawa

Introduced: 17 May 2023

CVE-2023-28321  (opens in a new tab)
CWE-295  (opens in a new tab)

How to fix?

Upgrade libcurl to version 8.1.1 or higher.

Overview

Affected versions of this package are vulnerable to Improper Certificate Validation such that IDN hostnames are converted to puny code before used for certificate checks. Puny coded names always start with xn-- and should not be allowed to pattern match, but the wildcard check in curl could still check for x*, which would match even though the IDN name most likely contained nothing even resembling an x.

CVSS Base Scores

version 3.1