CVE-2026-11856
Fixed in a distro release EPSS <1%CVSS 9.8
Successfully using libcurl to do a transfer to a specific HTTP origin (`hostA`) with **Digest** authentication and then changing the origin to a different one (`hostB`) for a second transfer, reusing the same handle, makes libcurl wrongly pass on the `Authorization:` header field meant for `hostA`, to `hostB`.
Products: curl
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux 10 | curl | 8.12.1-4.el10_2.6 |
| AlmaLinux 10 | libcurl | 8.12.1-4.el10_2.6 |
| AlmaLinux 10 | libcurl-devel | 8.12.1-4.el10_2.6 |
| AlmaLinux 10 | libcurl-minimal | 8.12.1-4.el10_2.6 |
| AlmaLinux 9 | curl | 7.76.1-40.el9_8.8 |
| AlmaLinux 9 | curl-minimal | 7.76.1-40.el9_8.8 |
| AlmaLinux 9 | libcurl | 7.76.1-40.el9_8.8 |
| AlmaLinux 9 | libcurl-devel | 7.76.1-40.el9_8.8 |
| AlmaLinux 9 | libcurl-minimal | 7.76.1-40.el9_8.8 |
| Alpine 3.23 | curl | 8.22.0-r0 |
| Alpine 3.24 | curl | 8.21.0-r0 |
| Amazon Linux 2023 | curl | 8.21.0-5.amzn2023.0.1 |
| Amazon Linux 2023 | curl-minimal | 8.21.0-5.amzn2023.0.1 |
| Amazon Linux 2023 | libcurl | 8.21.0-5.amzn2023.0.1 |
| Amazon Linux 2023 | libcurl-devel | 8.21.0-5.amzn2023.0.1 |
| Amazon Linux 2023 | libcurl-minimal | 8.21.0-5.amzn2023.0.1 |
| 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 |
| Debian 12 | curl | no fix |
| Debian 13 | curl | no fix |
| Debian 14 | curl | 8.21.0~rc3-1 |
| Red Hat Enterprise Linux 10.2 | curl | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | curl-debuginfo | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | curl-debugsource | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | libcurl | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | libcurl-debuginfo | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | libcurl-devel | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | libcurl-minimal | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 10.2 | libcurl-minimal-debuginfo | 0:8.12.1-4.el10_2.6 |
| Red Hat Enterprise Linux 9 | curl | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | curl-debuginfo | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | curl-debugsource | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | curl-minimal | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | curl-minimal-debuginfo | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | libcurl | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | libcurl-debuginfo | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | libcurl-devel | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | libcurl-minimal | 0:7.76.1-40.el9_8.8 |
| Red Hat Enterprise Linux 9 | libcurl-minimal-debuginfo | 0:7.76.1-40.el9_8.8 |
| 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_2.6 |
| Rocky Linux 9 | curl | 0:7.76.1-40.el9_8.8 |
| Ubuntu 22.04 LTS | curl | 7.81.0-1ubuntu1.26 |
| Ubuntu 24.04 LTS | curl | 8.5.0-2ubuntu10.12 |
| Ubuntu 25.10 | curl | no fix |
| Ubuntu 26.04 LTS | curl | 8.18.0-1ubuntu2.4 |
| Ubuntu Pro 14.04 LTS | curl | 7.35.0-1ubuntu2.20+esm22 |
| Ubuntu Pro 16.04 LTS | curl | 7.47.0-1ubuntu2.19+esm18 |
| Ubuntu Pro 18.04 LTS | curl | 7.58.0-2ubuntu3.24+esm11 |
| Ubuntu Pro 20.04 LTS | curl | 7.68.0-1ubuntu2.25+esm6 |
| openSUSE Tumbleweed | curl | 8.21.0-1.1 |