Medium [CVE-2026-44889] Open Redirect vulnerability via HTTP Location header normalization
This medium-severity Red Hat Linux advisory covers CVE-2026-44889 affecting Red Hat Enterprise Linux 6, Red Hat package: python-webob.
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
WebOb provides objects for HTTP requests and responses.
Prior to 1.8.10, the normalization of the HTTP Location header during a redirect is vulnerable to an open redirect: WebOb joins the redirect target to the request URI using Python's urljoin, and since Python 3.10 the underlying urlsplit strips ASCII tab, carriage return, and newline characters before parsing, so a redirect target containing such characters can be reinterpreted as a protocol-relative URL whose authority is an attacker-controlled host.
This bypasses the CVE-2024-42353 fix that escaped a leading double slash, allowing an attacker who influences the redirect location to send users to an arbitrary external site instead of the intended one. This vulnerability is fixed in 1.8.10.
Due to improper normalization of the Location header, specifically how certain ASCII characters are handled, an attacker can cause a user to be redirected to an arbitrary external website instead of the intended destination. This open redirect vulnerability can lead to information disclosure and impact the integrity of user sessions.
This is rated as Moderate (CVSS 6.1) because exploitation requires user interaction — a victim must click a crafted link that triggers the redirect (UI:R).
Affected products named by the advisory: Red Hat Enterprise Linux 6; Red Hat package: python-webob.
- < 1.8.10
- < 3.10
Official advisory · high-confidence parse· fetched 15 days ago·verify at source
Mitigation checklist
- This vulnerability in WebOb is only exploitable when running under Python 3.10 or later, where urllib.parse.urlsplit strips ASCII tab, carriage return, and newline characters before parsing. Red Hat Enterprise Linux, OpenShift Container Platform, Red Hat OpenStack Platform, Red Hat Ceph Storage, and Red Hat Quay all ship python-webob with Python 3.9 or earlier as the platform Python runtime, and are therefore not affected by this vulnerability. Fedora and EPEL ship python-webob under Python 3.12+, where the vulnerability is exploitable. Users running WebOb on Python 3.10+ should upgrade to WebOb 1.8.10. As a workaround, applications can validate that redirect targets start with a scheme (e.g. http:// or https://) and the expected host before assigning to Response.location.
Official advisory · high-confidence parse· fetched 15 days ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.