WebOb: Location header normalization during redirect leads to open redirect

6.1 / 10

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

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.

Basic Information

ID CVE-2026-44889

Source GitHub_M

Published Jun 22, 2026 at 21:30

Affected Product

Vendor Pylons

Product webob

Version < 1.8.10

Affected Versions Pylons webob < 1.8.10

CWE Classification

CWE-601

References

github.com /Pylons/webob/security/advisories/GHSA-fh3h-vg37-cc95

{
    "lastseen": "",
    "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.",
    "published": "2026-06-22T21:30:11.789Z",
    "modified": "2026-06-22T21:30:11.789Z",
    "type": "cve",
    "title": "WebOb: Location header normalization during redirect leads to open redirect",
    "source": "GitHub_M",
    "references": "https://github.com/Pylons/webob/security/advisories/GHSA-fh3h-vg37-cc95",
    "id": "CVE-2026-44889",
    "bulletinFamily": "",
    "cwe": [
        "CWE-601"
    ],
    "cvelist": null,
    "sourceData": "Pylons webob < 1.8.10",
    "sourceHref": "",
    "cvss": {
        "score": 6.1,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "webob",
    "version": "< 1.8.10",
    "vendor": "Pylons",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}

WebOb: Location header normalization during redirect leads to open redirect_CVE-2026-44889