Use-after-free in cURL - CVE-2026-80229

Vulnerability identifier: #VU146682

CSH Severity: Low

CVSS v4: 2.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-80229

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote user to cause a denial of service.

The vulnerability exists due to use-after-free in libcurl multi interface connection reuse handling when performing transfers over pooled TLS connections with OpenSSL 3 providers. A remote user can trigger premature easy handle destruction during connection reuse to cause a denial of service.

This affects libcurl built with OpenSSL 3+ provider configurations and also impacts the curl command line tool.

cURL
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Micro
SUSE Linux Enterprise Micro for Rancher
Basesystem Module
openSUSE Leap
Ubuntu
Fedora
libcurl4
libcurl-devel
libcurl4-debuginfo
libcurl4-debuginfo-32bit
curl
libcurl4-32bit
curl-debugsource
curl-debuginfo
libcurl4-64bit-debuginfo
libcurl4-64bit
libcurl-devel-64bit
libcurl-devel-doc
curl-zsh-completion
libcurl-devel-32bit
libcurl4-32bit-debuginfo
libcurl-mini4
libcurl-mini4-debuginfo
curl-mini-debugsource
curl-fish-completion
curl (Ubuntu package)

Install security update from vendor's website.

cURL - update to 8.22.0
libcurl4 - addressed in versions 8.0.1-11.129.1, 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
libcurl-devel - addressed in versions 8.0.1-11.129.1, 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
libcurl4-debuginfo - addressed in versions 8.0.1-11.129.1, 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
libcurl4-debuginfo-32bit - update to 8.0.1-11.129.1
curl - addressed in versions 8.0.1-11.129.1, 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
libcurl4-32bit - addressed in versions 8.0.1-11.129.1, 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
curl-debugsource - addressed in versions 8.0.1-11.129.1, 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
curl-debuginfo - addressed in versions 8.0.1-11.129.1, 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
libcurl4-64bit-debuginfo - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
libcurl4-64bit - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
libcurl-devel-64bit - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
libcurl-devel-doc - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
curl-zsh-completion - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
libcurl-devel-32bit - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
libcurl4-32bit-debuginfo - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1, 8.14.1-150700.7.26.1
libcurl-mini4 - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
libcurl-mini4-debuginfo - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
curl-mini-debugsource - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
curl-fish-completion - addressed in versions 8.14.1-150400.5.91.1, 8.14.1-150600.4.51.1
curl - addressed in versions 8.15.0-11.fc43, 8.15.0-12.fc43, 8.18.0-12.fc44, 8.21.0-7.fc45
curl (Ubuntu package) - addressed in versions 7.47.0-1ubuntu2.19+esm20, 7.58.0-2ubuntu3.24+esm14, 7.68.0-1ubuntu2.25+esm9, 7.81.0-1ubuntu1.29, 8.5.0-2ubuntu10.15, 8.18.0-1ubuntu2.7

• https://curl.se/docs/CVE-2026-80229.html
• https://github.com/curl/curl/commit/7ea37abc6ac0120ba5f6d9

• Multiple vulnerabilities in cURL
• SUSE update for curl
• SUSE update for curl
• SUSE update for curl
• SUSE update for curl
• Ubuntu update for curl
• Fedora 45 update for curl
• Fedora 44 update for curl
• Fedora 43 update for curl
• Fedora 43 update for curl