Description
libcurl keeps previously used connections in a connection pool for subsequenttransfers to reuse, if one of them matches the setup.Due to errors in the logic, the config matching function did not take 'issuercert' into account and it compared the involved paths *case insensitively*,which could lead to libcurl reusing wrong connections.File paths are, or can be, case sensitive on many systems but not all, and caneven vary depending on used file systems.The comparison also didn't include the 'issuer cert' which a transfer can setto qualify how to verify the server certificate.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | https://github.com/curl/curl | curl 7.10.4 to and include curl 7.77.0 | — |
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 | 7.79.1-1 | — |
| Debian 13 | curl | 7.79.1-1 | — |
| Debian 12 | curl | 7.79.1-1 | — |
| Debian 11 | curl | 7.74.0-1.3+deb11u2 | DSA-5197-1 |
| Debian 10 | curl | 7.64.0-4+deb10u3 | DLA-3085-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 9 | curl | 7.52.1-5+deb9u15 | DLA-2734-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | curl | 7.68.0-1ubuntu2.6 | USN-5021-1 |
| Ubuntu 18.04 LTS | curl | 7.58.0-2ubuntu3.14 | USN-5021-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 16.04 LTS | curl | No fix yet | — |
| Ubuntu Pro 14.04 LTS | curl | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | curl +3 | 7.61.1-18.el8_4.1 | RHSA-2021:3582 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Rhel Dotnet 3 | rh-dotnet31-curl +2 | 7.61.1-22.el7_9 | RHSA-2022:1354 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | curl | 7.61.1-18.el8_4.1 | RLSA-2021:3582 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP3 | curl | 7.66.0-4.22.1 | SUSE-SU-2021:2439-1 |
| SLES 15 SP2 | curl | 7.66.0-4.22.1 | SUSE-SU-2021:2439-1 |
| SLES 15 SP1 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SLES 15 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SLES 12 SP5 | curl | 7.60.0-11.23.1 | SUSE-SU-2021:2462-1 |
Show 15 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP4 | curl | 7.60.0-4.25.1 | SUSE-SU-2021:2425-1 |
| SLES 11 | curl-openssl1 | 7.37.0-70.71.1 | SUSE-SU-2021:14768-1 |
| SLES for SAP 15 SP1 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SLES for SAP 15 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SLES for SAP 12 SP5 | curl | 7.60.0-11.23.1 | SUSE-SU-2021:2462-1 |
| SLES for SAP 12 SP4 | curl | 7.60.0-4.25.1 | SUSE-SU-2021:2425-1 |
| SLE Micro 5.0 | curl | 7.66.0-4.22.1 | SUSE-SU-2021:2439-1 |
| SLE HPC 15 SP1 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SLE HPC 15 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SUSE OpenStack Cloud Crowbar 9 | curl | 7.60.0-4.25.1 | SUSE-SU-2021:2425-1 |
| SUSE OpenStack Cloud 9 | curl | 7.60.0-4.25.1 | SUSE-SU-2021:2425-1 |
| SUSE Manager Server 4.0 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SUSE Manager Retail Branch Server 4.0 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SUSE Manager Proxy 4.0 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
| SUSE Enterprise Storage 6 | curl | 7.60.0-3.47.1 | SUSE-SU-2021:2440-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | curl | 7.79.1-1.1 | openSUSE-SU-2024:10582-1 |
| openSUSE Leap 15.3 | curl | 7.66.0-4.22.1 | openSUSE-SU-2021:2439-1 |
| openSUSE Leap 15.2 | curl +1 | 7.66.0-lp152.3.21.1 | openSUSE-SU-2021:1088-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | curl | 7.78.0-r0 | — |
| Alpine v3.23 | curl | 7.78.0-r0 | — |
| Alpine v3.22 | curl | 7.78.0-r0 | — |
| Alpine v3.21 | curl | 7.78.0-r0 | — |
| Alpine v3.20 | curl | 7.78.0-r0 | — |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | curl | 7.78.0-r0 | — |
| Alpine v3.18 | curl | 7.78.0-r0 | — |
| Alpine v3.17 | curl | 7.78.0-r0 | — |
| Alpine v3.16 | curl | 7.78.0-r0 | — |
| Alpine v3.15 | curl | 7.78.0-r0 | — |
| Alpine v3.14 | curl | 7.78.0-r0 | — |
| Alpine v3.13 | curl | 7.78.0-r0 | — |
| Alpine v3.12 | curl | 7.78.0-r0 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | curl +2 | 7.76.1-7.amzn2.0.2 | ALAS2-2021-1700 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | curl | 7.76.0-5 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | curl +3 | 7.61.1-18.el8_4.1 | ELSA-2021-3582 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 1 repository
-
Trinadh465/external_curl_AOSP10_r33_CVE-2021-22924 ★ 0 · Apr 30, 2022
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 30
- RHSA-2021:3582 Red Hat Security Advisory: curl security update Red Hat Security Advisories (RHSA) · Oct 15, 2026
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- RHSA-2022:1354 Red Hat Security Advisory: rh-dotnet31-curl security update Red Hat Security Advisories (RHSA) · Sep 21, 2026
- WID-SEC-2023-1350 Splunk Splunk Enterprise: Mehrere Schwachstellen in Komponenten von Drittanbietern BSI CERT-Bund (WID) · Jul 1, 2026
- USN-5021-1 curl vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- DSA-5197-1 curl - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2734-1 curl - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3085-1 curl - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2021:3582 Moderate: curl security update Rocky Linux Security Advisories · Feb 4, 2026
- openSUSE-SU-2024:10582-1 curl-7.79.1-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:2462-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:14768-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:2440-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:2439-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2021:2425-1 Security update for curl SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:1088-1 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-2023-2229 Splunk Splunk Enterprise: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 18, 2025
- ALAS2-2021-1700 Moderate: curl security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Sep 23, 2025
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- openSUSE-SU-2021:2439-1 Security update for curl SUSE / openSUSE Security Updates · May 7, 2025
- ICSA-22-069-09 Siemens SINEC INS CISA ICS & IT advisories · May 6, 2025
- WID-SEC-2024-0556 Sophos Unified Threat Management (UTM) Software: Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 8, 2024
- SSA-484086 SSA-484086: Multiple Vulnerabilities in SINEMA Remote Connect Server before V3.1 Siemens ProductCERT · Jul 9, 2024
- ICSA-22-167-17 Siemens OpenSSL Affecting Industrial Products CISA ICS & IT advisories · Jul 9, 2024
- WID-SEC-2022-0874 cURL: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jul 4, 2023
- SSA-732250 SSA-732250: Libcurl Vulnerabilities in Industrial Devices Siemens ProductCERT · Aug 9, 2022
- ICSA-22-132-13 Siemens Industrial Devices using libcurl CISA ICS & IT advisories · Aug 9, 2022
- SSA-389290 SSA-389290: Third-Party Component Vulnerabilities in SINEC INS Siemens ProductCERT · Mar 8, 2022
- ELSA-2021-3582 Moderate: curl security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Sep 21, 2021
References
- https://hackerone.com/reports/1223565
- FEDORA-2021-5d21b90a30 vendor-advisory
- [debian-lts-announce] 20210813 [SECURITY] [DLA 2734-1] curl security update mailing-list
- [kafka-dev] 20210831 Security vulnerabilities in kafka:2.13-2.6.0/2.7.0 docker image mailing-list
- [kafka-users] 20210831 Security vulnerabilities in kafka:2.13-2.6.0/2.7.0 docker image mailing-list
- [kafka-users] 20210901 Re: [EXTERNAL] Re: Security vulnerabilities in kafka:2.13-2.6.0/2.7.0 docker image mailing-list
- [kafka-dev] 20210901 Re: [EXTERNAL] Re: Security vulnerabilities in kafka:2.13-2.6.0/2.7.0 docker image mailing-list
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://security.netapp.com/advisory/ntap-20210902-0003/
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-732250.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-484086.pdf
- DSA-5197 vendor-advisory
- [debian-lts-announce] 20220828 [SECURITY] [DLA 3085-1] curl security update mailing-list