# CVE-2026-44431: urllib3 β€” Fixed in 2.7.0 🐍 PyPI Not in CISA KEV # CVE-2026-44431 β€” urllib3 CVE-2026-44431 is a Information Exposure vulnerability in urllib3. A fix is available for urllib3 β€” see the affected versions and patch details below. urllib3: Sensitive headers forwarded across origins in proxied low-level redirects Also known as[GHSA-qccp-gfcp-xxvc](/vulnerability/GHSA-qccp-gfcp-xxvc)PYSEC-2026-141 Published May 13, 2026 Updated Oct 28, 2026 Affected 1 pkg Patched 1 / 1 Exploits None indexed Exploitation data as of Nov 10, 2026 Β· OSV.dev, NVD, FIRST.org (EPSS) ## Exploitation Status ### No confirmed exploitation observed yet - CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment. Exploitation and automatability from CISA’s SSVC triage for CVE-2026-44431. ## EPSS Exploitation Probability [via FIRST.org β†—](https://www.first.org/epss/) 0.3%probability of exploitation in next 30 days Lower Risk0.00% Lower risk than most CVEs27th percentile β€” riskier than 27% of all scored CVEsHighest risk 0.00%0.34%0.68%1.03%0.0%0.3%Jun 26Sep 26Nov 26 Probability of exploitation in the next 30 days, from [FIRST.org EPSS](https://www.first.org/epss/). ## Real-World Exposure 1 pkg affected 🐍`urllib3` Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages β€” download data is not available via public APIs for these ecosystems. ## Description #### Impact When following cross-origin redirects for requests made using urllib3’s high-level APIs, such as `urllib3.request()`, `PoolManager.request()`, and `ProxyManager.request()`, sensitive headers β€” `Authorization`, `Cookie`, and `Proxy-Authorization` (defined in `Retry.DEFAULT_REMOVE_HEADERS_ON_REDIRECT`) β€” are stripped by default, as expected. However, cross-origin redirects followed from the low-level API via `ProxyManager.connection_from_url().urlopen(..., assert_same_host=False)` still forward these sensitive headers. #### Affected usage Applications and libraries using urllib3 versions earlier than 2.7.0 may be affected if they allow cross-origin redirects while making requests through `HTTPConnection.urlopen()` instances created via `ProxyManager.connection_from_url()`. #### Remediation Upgrade to urllib3 version 2.7.0 or later, in which sensitive headers are stripped from redirects followed by `HTTPConnection`. If upgrading is not immediately possible, avoid using this low-level redirect flow for cross-origin redirects. If appropriate for your use case, switch to `ProxyManager.request()`. ## Affected Packages 1 total 1 fixed Ecosystem Package Vulnerable range Fix 🐍PyPI `urllib3` β‰₯ 1.23&&< 2.7.0 2.7.0`pip install --upgrade 'urllib3==2.7.0'` ## Affected Products 1 product Β· 1 configurations Application `urllib3`python β‰₯ 1.23 && < 2.7.0 range ## Detection & mitigation playbook Open-source dependency 1. ### Detect Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for urllib3, including transitive dependencies β€” a direct dependency you never call can still pull in a vulnerable version. 2. ### Fix Update urllib3 to 2.7.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range β€” O3 confirms CVE-2026-44431 is resolved across your whole dependency graph. 3. ### Workarounds Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them. ## Fixing This On Your OS If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below β€” it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project. Red HatModerate Product Fixed in Advisory Red Hat Ansible Automation Platform 2.6 for RHEL 9 `python3.12-urllib3-0:2.7.0-1.el9ap` [RHSA-2026:34160](https://access.redhat.com/errata/RHSA-2026:34160) Red Hat Enterprise Linux 10 `python3.14-urllib3-0:2.6.3-2.el10_2` [RHSA-2026:27929](https://access.redhat.com/errata/RHSA-2026:27929) Red Hat Enterprise Linux 10 `python-urllib3-0:1.26.19-4.el10_2` [RHSA-2026:28000](https://access.redhat.com/errata/RHSA-2026:28000) Red Hat Enterprise Linux 8 `python3.12-urllib3-0:1.26.19-3.el8_10` [RHSA-2026:32992](https://access.redhat.com/errata/RHSA-2026:32992) Red Hat Enterprise Linux 8 `fence-agents-0:4.2.1-129.el8_10.28` [RHSA-2026:49927](https://access.redhat.com/errata/RHSA-2026:49927) Red Hat Enterprise Linux 8 `resource-agents-0:4.9.0-54.el8_10.36` [RHSA-2026:47126](https://access.redhat.com/errata/RHSA-2026:47126) Red Hat Enterprise Linux 8 `python-urllib3-0:1.24.2-10.el8_10` [RHSA-2026:36732](https://access.redhat.com/errata/RHSA-2026:36732) Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support `fence-agents-0:4.2.1-65.el8_4.31` [RHSA-2026:51152](https://access.redhat.com/errata/RHSA-2026:51152) ## Frequently Asked Questions \### Impact When following cross-origin redirects for requests made using urllib3’s high-level APIs, such as \`urllib3.request()\`, \`PoolManager.request()\`, and \`ProxyManager.request()\`, sensitive headers β€” \`Authorization\`, \`Cookie\`, and \`Proxy-Authorization\` (defined in \`Retry.DEFAULT\_REMOVE\_HEADERS\_ON\_REDIRECT\`) β€” are stripped by default, as expected. However, cross-origin redirects followed from the low-level API via \`ProxyManager.connection\_from\_url().urlopen(..., assert\_same\_host=False)\` still forward these sensitive headers. ### Affected usage Applications and libraries using urllib3 ve O3 Security Β· Impact-Aware SCA ### Is CVE-2026-44431 in your dependencies? Find it across PyPI, including transitive dependencies. [Scan my dependencies](/book-demo) [How O3 SCA works](/impact-aware-sca)