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.
CVE-2026-55553
This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 70% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(medium)
- EG Risk
- 65(Attend)EG Risk 65/100SSVC: Attend
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity75% × 45%Exploitation40% × 40%Automatability100% × 15%Action: Remediate soon — notable exploitation risk. - EPSS PROB
- 0%
- EPSS %ILE
- 30%
- KEV
- Not listed
Published
August 25, 2026
Last Modified
August 25, 2026
Advisory Details (7)
Auto-updated Aug 25, 2026v4.9.1
Patch available: node-modules/urllib v4.9.1
https://github.com/node-modules/urllib/releases/tag/v4.9.1v2.44.1
Patch available: node-modules/urllib v2.44.1
https://github.com/node-modules/urllib/releases/tag/v2.44.1commit 811a8d56e64e (node-modules/urllib)
Patch available: node-modules/urllib v4.9.1 (contains commit 811a8d56e64e)
https://github.com/node-modules/urllib/commit/811a8d56e64e540bf6a19bf8b3737692f05d5c46commit 7c86c465883e (node-modules/urllib)
Patch available: node-modules/urllib v2.44.1 (contains commit 7c86c465883e)
https://github.com/node-modules/urllib/commit/7c86c465883ebd3dea5109c87d7bbe3b00960a16fix: do not forward credential headers on cross-origin redirect
Patch available: node-modules/urllib v2.44.1 (PR #813 merged 2026-06-13)
https://github.com/node-modules/urllib/pull/813fix: do not forward credential headers on cross-origin redirect
Patch available: node-modules/urllib v4.9.1 (PR #812 merged 2026-06-13)
https://github.com/node-modules/urllib/pull/812Cross-origin redirects preserve credential-bearing request headers, leading to potential credential leakage · Advisory · node-modules/urllib · GitHub
https://github.com/node-modules/urllib/security/advisories/GHSA-hq3h-g68c-hp78Vendor Advisories for CVE-2026-55553(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
npm(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| urllib | — | 4.9.1 | — |
Weakness Classification(3)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 13× in last 7d / 13× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-30 04:57 UTCEG score recompute
- 2026-08-30 01:22 UTCEPSS rescore
- 2026-08-29 05:02 UTCEG score recompute
- 2026-08-28 21:41 UTCEPSS rescore
- 2026-08-27 18:11 UTCEG score recompute
- 2026-08-27 14:25 UTCEPSS rescore
- 2026-08-26 18:26 UTCEG score recompute
- 2026-08-26 14:46 UTCEPSS rescore
- 2026-08-25 19:21 UTCEG score recompute
- 2026-08-25 18:30 UTCEG score recompute
- 2026-08-25 17:25 UTCEG score recompute
- 2026-08-25 16:25 UTCEG score recompute
- 2026-08-25 16:24 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-55553?
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How do I remediate CVE-2026-55553?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-55553
Is Your Infrastructure Affected by CVE-2026-55553?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.