Description
An improper certificate validation vulnerability exists in curl <v8.1.0 in the way it supports matching of wildcard patterns when listed as "Subject Alternative Name" in TLS server certificates. curl can be built to use its own name matching function for TLS rather than one provided by a TLS library. This private wildcard matching function would match IDN (International Domain Name) hosts incorrectly and could as a result accept patterns that otherwise should mismatch. 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`.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | https://github.com/curl/curl | Fixed in 8.1.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | curl | 7.88.1-10 | — |
| Debian 13 | curl | 7.88.1-10 | — |
| Debian 12 | curl | 7.88.1-10 | — |
| Debian 10 | curl | 7.64.0-4+deb10u7 | DLA-3613-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | curl | 7.81.0-1ubuntu1.11 | USN-6237-1 |
| Ubuntu 20.04 LTS | curl | 7.68.0-1ubuntu2.19 | USN-6237-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | curl | 7.58.0-2ubuntu3.24+esm1 | USN-6237-3 |
| Ubuntu Pro 16.04 LTS | curl | 7.47.0-1ubuntu2.19+esm9 | USN-6237-3 |
| Ubuntu Pro 14.04 LTS | curl | 7.35.0-1ubuntu2.20+esm16 | USN-6237-3 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | curl +4 | 7.76.1-23.el9_2.2 | RHSA-2023:4354 |
| RHEL 8 | curl +3 | 7.61.1-30.el8_8.3 | RHSA-2023:4523 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.0 EUS | curl +4 | 7.76.1-14.el9_0.7 | RHSA-2023:5598 |
| RHEL 8.6 EUS | curl +3 | 7.61.1-22.el8_6.9 | RHSA-2023:6292 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-apr +1 | 1.7.0-8.el7jbcs | RHSA-2023:4629 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-curl +2 | 8.2.1-1.el7jbcs | RHSA-2023:4629 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-httpd +6 | 2.4.57-5.el7jbcs | RHSA-2023:4629 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_security | 2.9.3-29.el7jbcs | RHSA-2023:4629 |
| Red Hat JBoss Core Services 1 | jbcs-httpd24-mod_ssl +1 | 1:2.4.57-5.el7jbcs | RHSA-2023:4629 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 9 | curl +4 | 7.76.1-23.el9_2.2 | ALSA-2023:4354 |
| AlmaLinux 8 | curl +3 | 7.61.1-30.el8_8.3 | ALSA-2023:4523 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | curl | 7.61.1-30.el8_8.3 | RLSA-2023:4523 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP4 | curl | 8.0.1-150400.5.23.1 | SUSE-SU-2023:2224-1 |
| SLES 15 SP3 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLES 15 SP2 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLES 15 SP1 | curl | 7.60.0-150000.51.1 | SUSE-SU-2023:2226-1 |
| SLES 12 SP5 | curl | 8.0.1-11.65.2 | SUSE-SU-2023:2225-1 |
Show 22 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP4 | curl | 7.60.0-4.56.1 | SUSE-SU-2023:2228-1 |
| SLES 12 SP2 | curl | 7.37.0-37.98.1 | SUSE-SU-2023:2230-1 |
| SLES for SAP 15 SP3 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLES for SAP 15 SP2 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLES for SAP 15 SP1 | curl | 7.60.0-150000.51.1 | SUSE-SU-2023:2226-1 |
| SLES for SAP 12 SP5 | curl | 8.0.1-11.65.2 | SUSE-SU-2023:2225-1 |
| SLES for SAP 12 SP4 | curl | 7.60.0-4.56.1 | SUSE-SU-2023:2228-1 |
| SLE Real Time 15 SP3 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLE Micro 5.4 | curl | 8.0.1-150400.5.23.1 | SUSE-SU-2023:2224-1 |
| SLE Micro 5.3 | curl | 8.0.1-150400.5.23.1 | SUSE-SU-2023:2224-1 |
| SLE Micro 5.2 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLE Micro 5.1 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLE HPC 15 SP3 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLE HPC 15 SP2 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SLE HPC 15 SP1 | curl | 7.60.0-150000.51.1 | SUSE-SU-2023:2226-1 |
| SUSE OpenStack Cloud Crowbar 9 | curl | 7.60.0-4.56.1 | SUSE-SU-2023:2228-1 |
| SUSE OpenStack Cloud 9 | curl | 7.60.0-4.56.1 | SUSE-SU-2023:2228-1 |
| SUSE Manager Server 4.2 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SUSE Manager Proxy 4.2 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SUSE Enterprise Storage 7.1 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SUSE Enterprise Storage 7 | curl | 7.66.0-150200.4.57.1 | SUSE-SU-2023:2227-1 |
| SUSE Enterprise Storage 6 | curl | 7.60.0-150000.51.1 | SUSE-SU-2023:2226-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | curl | 8.1.0-1.1 | openSUSE-SU-2024:12940-1 |
| openSUSE Leap 15.5 | curl | 8.0.1-150400.5.23.1 | SUSE-SU-2023:2224-2 |
| openSUSE Leap 15.4 | curl | 8.0.1-150400.5.23.1 | SUSE-SU-2023:2224-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap Micro 5.3 | curl | 8.0.1-150400.5.23.1 | SUSE-SU-2023:2224-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | curl | 8.1.0-r0 | — |
| Alpine v3.23 | curl | 8.1.0-r0 | — |
| Alpine v3.22 | curl | 8.1.0-r0 | — |
| Alpine v3.21 | curl | 8.1.0-r0 | — |
| Alpine v3.20 | curl | 8.1.0-r0 | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | curl | 8.1.0-r0 | — |
| Alpine v3.18 | curl | 8.1.0-r0 | — |
| Alpine v3.17 | curl | 8.1.0-r0 | — |
| Alpine v3.16 | curl | 8.1.0-r0 | — |
| Alpine v3.15 | curl | 8.1.0-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | curl +4 | 8.0.1-1.amzn2023.0.1 | ALAS2023-2023-270 |
| Amazon Linux 2 | curl +2 | 8.2.1-1.amzn2.0.2 | ALAS2-2023-2230 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | tensorflow | 2.16.1-1 | — |
| Azure Linux 2 (CBL-Mariner) | curl | 8.2.1-1 | — |
| Azure Linux 2 (CBL-Mariner) | mysql | 8.0.34-1 | — |
| Azure Linux 2 (CBL-Mariner) | rust | 1.72.0-2 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | curl +4 | 7.76.1-23.el9_2.2 | ELSA-2023-4354 |
| Oracle Linux 8 | curl +3 | 7.61.1-30.el8_8.3 | ELSA-2023-4523 |
Advisories 33
- ALSA-2023:4354 Moderate: curl security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2023:4523 Moderate: curl security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2023:4523 Red Hat Security Advisory: curl security update Red Hat Security Advisories (RHSA) · Oct 15, 2026
- RHSA-2023:6292 Red Hat Security Advisory: curl security update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- RHSA-2023:5598 Red Hat Security Advisory: curl security update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- RHSA-2023:4629 Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.57 security update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- RHSA-2023:4354 Red Hat Security Advisory: curl security update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- WID-SEC-2024-0794 Dell ECS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 11, 2026
- WID-SEC-2023-2917 Xerox FreeFlow Print Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jun 30, 2026
- USN-6237-3 curl vulnerabilities Ubuntu Security Notices (USN) · Jun 29, 2026
- USN-6237-1 curl vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DLA-3613-1 curl - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2023:4523 Moderate: curl security update Rocky Linux Security Advisories · Feb 4, 2026
- SUSE-SU-2023:2226-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2224-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:12940-1 curl-8.1.0-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2225-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2230-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2228-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2227-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2224-2 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2026-0180 Dell Data Protection Advisor: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jan 20, 2026
- WID-SEC-2023-1237 cURL: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 6, 2025
- WID-SEC-2024-3377 Dell PowerProtect Data Domain: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 12, 2025
- WID-SEC-2024-0556 Sophos Unified Threat Management (UTM) Software: Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 8, 2024
- ICSA-24-046-15 Siemens SINEC NMS CISA ICS & IT advisories · Mar 12, 2024
- SSA-943925 SSA-943925: Multiple Vulnerabilities in SINEC NMS before V2.0 SP1 Siemens ProductCERT · Mar 12, 2024
- WID-SEC-2023-1614 Tenable Security Nessus Network Monitor: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 25, 2023
- WID-SEC-2023-1880 Apple macOS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 11, 2023
- ALAS2-2023-2230 Moderate: curl security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Sep 7, 2023
- ELSA-2023-4523 Moderate: curl security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Aug 10, 2023
- ELSA-2023-4354 Moderate: curl security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Aug 2, 2023
- ALAS2023-2023-270 Moderate: curl security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jul 26, 2023
References
- https://hackerone.com/reports/1950627
- FEDORA-2023-37eac50e9b vendor-advisory
- FEDORA-2023-8ed627bb04 vendor-advisory
- https://security.netapp.com/advisory/ntap-20230609-0009/
- https://support.apple.com/kb/HT213843
- https://support.apple.com/kb/HT213844
- https://support.apple.com/kb/HT213845
- 20230725 APPLE-SA-2023-07-24-6 macOS Big Sur 11.7.9 mailing-list
- 20230725 APPLE-SA-2023-07-24-5 macOS Monterey 12.6.8 mailing-list
- 20230725 APPLE-SA-2023-07-24-4 macOS Ventura 13.5 mailing-list
- GLSA-202310-12 vendor-advisory
- [debian-lts-announce] 20231011 [SECURITY] [DLA 3613-1] curl security update mailing-list