libcurl 8.13.0 < 8.21.0 Use-After-Free in Socket Callback

critical Nessus Plugin ID 323008

Synopsis

The remote host has a program that is affected by a use-after-free vulnerability.

Description

The version of libcurl installed on the remote host is 8.13.0 prior to 8.21.0. It is, therefore, affected by a use-after-free vulnerability:

- Calling curl_easy_pause() within the event-based CURLMOPT_SOCKETFUNCTION callback triggers a use-after-free vulnerability. (CVE-2026-9080)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade libcurl to version 8.21.0 or later.

See Also

https://curl.se/docs/CVE-2026-9080.html

Plugin Details

Severity: Critical

ID: 323008

File Name: libcurl_CVE-2026-9080.nasl

Version: 1.1

Type: Local

Agent: windows, macosx, unix

Family: Misc.

Published: 6/26/2026

Updated: 6/26/2026

Configuration: Enable thorough checks (optional)

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.4

CVSS v2

Risk Factor: High

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2026-9080

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Vulnerability Information

CPE: cpe:/a:haxx:libcurl

Required KB Items: installed_sw/libcurl

Patch Publication Date: 6/24/2026

Vulnerability Publication Date: 6/24/2026

Reference Information

CVE: CVE-2026-9080

IAVA: 2026-A-0627