CVE-2026-8927
Fixed in a distro release EPSS <1%CVSS 9.1
When reusing a libcurl handle for sequential transfers driven by environment-variable proxy configuration, libcurl fails to clear the proxy authentication state between requests. Specifically, if the initial transfer authenticates against `proxyA` using Digest auth, a subsequent transfer routed through `proxyB` erroneously leaks the `Proxy-Authorization:` header intended solely for `proxyA`.
Products: curl
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux 10 | curl | 8.12.1-4.el10_2.4 |
| AlmaLinux 10 | libcurl | 8.12.1-4.el10_2.4 |
| AlmaLinux 10 | libcurl-devel | 8.12.1-4.el10_2.4 |
| AlmaLinux 10 | libcurl-minimal | 8.12.1-4.el10_2.4 |
| AlmaLinux 9 | curl | 7.76.1-40.el9_8.7 |
| AlmaLinux 9 | curl-minimal | 7.76.1-40.el9_8.7 |
| AlmaLinux 9 | libcurl | 7.76.1-40.el9_8.7 |
| AlmaLinux 9 | libcurl-devel | 7.76.1-40.el9_8.7 |
| AlmaLinux 9 | libcurl-minimal | 7.76.1-40.el9_8.7 |
| Alpine 3.21 | curl | 8.14.1-r3 |
| Alpine 3.22 | curl | 8.14.1-r4 |
| Alpine 3.23 | curl | 8.22.0-r0 |
| Alpine 3.24 | curl | 8.21.0-r0 |
| Chainguard | eco-python-curl | 8.21.0-r0 |
| Chainguard | eco-python-curl-minimal | 8.21.0-r0 |
| Chainguard | eco-python-curl-minimal-bin | 8.21.0-r0 |
| Chainguard | eco-python-curl-minimal-dev | 8.21.0-r0 |
| Chainguard | eco-python-curl-minimal-doc | 8.21.0-r0 |
| Chainguard | eco-python-curl-minimal-static | 8.21.0-r0 |
| Chainguard | eco-python-curl-nghttp2 | 8.21.0-r0 |
| Chainguard | eco-python-curl-nghttp2-bin | 8.21.0-r0 |
| Chainguard | eco-python-curl-nghttp2-dev | 8.21.0-r0 |
| Chainguard | eco-python-curl-nghttp2-static | 8.21.0-r0 |
| Chainguard | libcurl4 | no fix |
| Debian 12 | curl | no fix |
| Debian 13 | curl | 8.14.1-2+deb13u7 |
| Debian 14 | curl | 8.21.0~rc2-1 |
| Red Hat Enterprise Linux 10.2 | curl | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | curl-debuginfo | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | curl-debugsource | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libcurl | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libcurl-debuginfo | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libcurl-devel | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libcurl-minimal | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 10.2 | libcurl-minimal-debuginfo | 0:8.12.1-4.el10_2.4 |
| Red Hat Enterprise Linux 9 | curl | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | curl-debuginfo | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | curl-debugsource | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | curl-minimal | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | curl-minimal-debuginfo | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | libcurl | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | libcurl-debuginfo | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | libcurl-devel | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | libcurl-minimal | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux 9 | libcurl-minimal-debuginfo | 0:7.76.1-40.el9_8.7 |
| Red Hat Enterprise Linux eus 10.0 | curl | 0:8.12.1-1.el10_0.10 |
| Red Hat Enterprise Linux eus 10.0 | curl-debuginfo | 0:8.12.1-1.el10_0.10 |
| Red Hat Enterprise Linux eus 10.0 | curl-debugsource | 0:8.12.1-1.el10_0.10 |
| Red Hat Enterprise Linux eus 10.0 | libcurl | 0:8.12.1-1.el10_0.10 |
| Red Hat Enterprise Linux eus 10.0 | libcurl-debuginfo | 0:8.12.1-1.el10_0.10 |
| Red Hat Enterprise Linux eus 10.0 | libcurl-devel | 0:8.12.1-1.el10_0.10 |
| Red Hat Enterprise Linux eus 10.0 | libcurl-minimal | 0:8.12.1-1.el10_0.10 |
| Red Hat Enterprise Linux eus 10.0 | libcurl-minimal-debuginfo | 0:8.12.1-1.el10_0.10 |
| Red Hat hummingbird 1 | cargo | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | clippy | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | curl | 0:8.21.0-0.1.hum1 |
| Red Hat hummingbird 1 | libcurl | 0:8.21.0-0.1.hum1 |
| Red Hat hummingbird 1 | libcurl-devel | 0:8.21.0-0.1.hum1 |
| Red Hat hummingbird 1 | libcurl-minimal | 0:8.21.0-0.1.hum1 |
| Red Hat hummingbird 1 | rust | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-analyzer | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-debugger-common | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-doc | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-gdb | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-lldb | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-src | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-aarch64-unknown-none-softfloat | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-aarch64-unknown-uefi | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-i686-pc-windows-gnu | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-wasm32-unknown-unknown | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-wasm32-wasip1 | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-x86_64-pc-windows-gnu | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-x86_64-unknown-none | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rust-std-static-x86_64-unknown-uefi | 0:1.96.1-1.hum1 |
| Red Hat hummingbird 1 | rustfmt | 0:1.96.1-1.hum1 |
| Rocky Linux 10 | curl | 0:8.12.1-4.el10_2.4 |
| Rocky Linux 9 | curl | 0:7.76.1-40.el9_8.7 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Installer Updates 15 SP4 | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Installer Updates 15 SP5 | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Micro 5.3 | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Micro 5.4 | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Micro 5.5 | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | curl | 8.14.1-150700.7.20.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | curl | 8.14.1-150400.5.86.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | curl | 8.14.1-150600.4.46.1 |
| SUSE Linux Enterprise Server 16.0 | curl | 8.14.1-160000.8.1 |
| SUSE Linux Enterprise Server 16.0 | curl-mini | 8.14.1-160000.8.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | curl | 8.14.1-150600.4.46.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | curl | 8.14.1-160000.8.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | curl-mini | 8.14.1-160000.8.1 |
| SUSE Linux Micro 6.0 | curl | 8.14.1-7.1 |
| SUSE Linux Micro 6.1 | curl | 8.14.1-slfo.1.1_8.1 |
| SUSE Linux Micro 6.2 | curl | 8.14.1-160000.8.1 |
| Ubuntu 22.04 LTS | curl | 7.81.0-1ubuntu1.29 |
| Ubuntu 22.04 LTS | curl | 7.81.0-1ubuntu1.25 |
| Ubuntu 24.04 LTS | curl | 8.5.0-2ubuntu10.15 |
| Ubuntu 24.04 LTS | curl | 8.5.0-2ubuntu10.10 |
| Ubuntu 25.10 | curl | 8.14.1-2ubuntu1.4 |
| Ubuntu 26.04 LTS | curl | 8.18.0-1ubuntu2.7 |
| Ubuntu 26.04 LTS | curl | 8.18.0-1ubuntu2.2 |
| Ubuntu Pro 14.04 LTS | curl | 7.35.0-1ubuntu2.20+esm20 |
| Ubuntu Pro 16.04 LTS | curl | 7.47.0-1ubuntu2.19+esm16 |
| Ubuntu Pro 16.04 LTS | curl | 7.47.0-1ubuntu2.19+esm20 |
| Ubuntu Pro 18.04 LTS | curl | 7.58.0-2ubuntu3.24+esm9 |
| Ubuntu Pro 18.04 LTS | curl | 7.58.0-2ubuntu3.24+esm14 |
| Ubuntu Pro 20.04 LTS | curl | 7.68.0-1ubuntu2.25+esm4 |
| Ubuntu Pro 20.04 LTS | curl | 7.68.0-1ubuntu2.25+esm9 |
| Wolfi | libcurl4 | no fix |
| openSUSE Leap 16.0 | curl | 8.14.1-160000.8.1 |
| openSUSE Tumbleweed | curl | 8.21.0-1.1 |