# CVE-2026-44889: WebOb: Location header normalization during redirect leads to open redirect > An attacker can manipulate redirect locations to send users to arbitrary external sites, bypassing previous security fixes in the WebOb library. - **Severity:** Medium 6.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 22 Jun 2026 - **Updated:** 23 Jun 2026 - **Also known as:** AZL-91362, DEBIAN-CVE-2026-44889, ECHO-0b2f-27c4-24aa, GHSA-fh3h-vg37-cc95, MGASA-2026-0452, OESA-2026-2679, PYSEC-2026-251, SUSE-SU-2026:22370-1, SUSE-SU-2026:2982-1, UBUNTU-CVE-2026-44889, openSUSE-SU-2026:11041-1, openSUSE-SU-2026:21063-1 ## What is CVE-2026-44889? CVE-2026-44889 is a medium-severity vulnerability in Pylons webob, published on 22 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. ### Official description 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. Weakness: CWE-601 (URL Redirection to Untrusted Site) ## Which versions are affected by CVE-2026-44889? 3 open source packages ship an affected version, including webob. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `webob` | PyPI | All versions | 1.8.10 | | `webob` | PyPI | All versions | 1.8.10 | | `webob` | PyPI | All versions | 1.8.10 | | `python-WebOb` | SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 1.7.4-150000.3.6.1 | | `python-WebOb` | SUSE:Linux Enterprise Module for Package Hub 15 SP7 | All versions | 1.7.4-150000.3.6.1 | | `python-Markdown` | SUSE:Linux Enterprise Server 16.0 | All versions | 3.8.2-160000.3.1 | | `python-PyGithub` | SUSE:Linux Enterprise Server 16.0 | All versions | 2.6.1-160000.3.1 | | `python-WebOb` | SUSE:Linux Enterprise Server 16.0 | All versions | 1.8.9-160000.3.1 | | `python-apache-libcloud` | SUSE:Linux Enterprise Server 16.0 | All versions | 3.8.0-160000.3.1 | | `python-handy-archives` | SUSE:Linux Enterprise Server 16.0 | All versions | 0.2.0-160000.3.1 | | `python-soupsieve` | SUSE:Linux Enterprise Server 16.0 | All versions | 2.6-160000.3.1 | | `python-Markdown` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 3.8.2-160000.3.1 | | `python-PyGithub` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 2.6.1-160000.3.1 | | `python-WebOb` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 1.8.9-160000.3.1 | | `python-apache-libcloud` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 3.8.0-160000.3.1 | | `python-handy-archives` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 0.2.0-160000.3.1 | | `python-soupsieve` | SUSE:Linux Enterprise Server for SAP applications 16.0 | All versions | 2.6-160000.3.1 | | `python-Markdown` | openSUSE:Leap 16.0 | All versions | 3.8.2-160000.3.1 | | `python-PyGithub` | openSUSE:Leap 16.0 | All versions | 2.6.1-160000.3.1 | | `python-WebOb` | openSUSE:Leap 16.0 | All versions | 1.8.9-160000.3.1 | | `python-apache-libcloud` | openSUSE:Leap 16.0 | All versions | 3.8.0-160000.3.1 | | `python-handy-archives` | openSUSE:Leap 16.0 | All versions | 0.2.0-160000.3.1 | | `python-joblib` | openSUSE:Leap 16.0 | All versions | 1.5.2-160000.1.1 | | `python-soupsieve` | openSUSE:Leap 16.0 | All versions | 2.6-160000.3.1 | | `python-WebOb` | openSUSE:Tumbleweed | All versions | 1.8.10-1.1 | Products: Pylonsproject Webob. ## How do I fix CVE-2026-44889? Upgrade webob to 1.8.10 or later. ## Is CVE-2026-44889 being exploited? There is no known exploitation of CVE-2026-44889 in the wild and no public exploit code. ## Other vulnerabilities in Pylons webob - [CVE-2024-42353](https://insights.sbomify.com/CVE-2024-42353/): WebOb's location header normalization during redirect leads to open redirect (medium 6.1) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-44889 and fix it if it is affected. What it is: CVE-2026-44889 is a medium-severity vulnerability in Pylons webob, published on 22 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2026-44889 in the wild and no public exploit code. Affected packages and fixed versions: - webob (PyPI): affected all versions; fixed in 1.8.10 - webob (PyPI): affected all versions; fixed in 1.8.10 - webob (PyPI): affected all versions; fixed in 1.8.10 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-44889/ (Markdown: https://insights.sbomify.com/CVE-2026-44889/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-44889 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-44889 - OSV: https://osv.dev/vulnerability/CVE-2026-44889 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-44889/ Summaries are generated and may contain mistakes; the official description above is the record.