CVE-2026-55553urllib: Cross-origin redirects preserve credential-bearing request headers, leading to potential credential leakage

urllib is an HTTP client for Node.js that supports authentication, redirects, timeouts, and other request features. Prior to 4.9.1 and 2.44.1, urllib follows redirects through followRedirect but reuses caller-supplied options across origins. In src/HttpClient.ts, #requestInternal recursively calls this.#requestInternal(nextUrl.href, options, requestContext), causing options.headers and auth or digestAuth values to be reused when the redirect target has a different scheme, host, or port. Authorization, Cookie, Proxy-Authorization, x-api-key, x-auth-token, and x-access-token can therefore be sent to an attacker-controlled redirected origin, exposing credentials intended for the original origin and potentially allowing reuse against the original partner API or related services. No user interaction is required. This issue is fixed in versions 2.44.1 and 4.9.1.

CVSS

7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Weakness (CWE)

CWE-200, CWE-201, CWE-522

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

GitHub_M

NVD analysis

Deferred

Record last updated

Aug 25, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.