undici.request vulnerable to SSRF using absolute URL on pathname

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS

• CVE-2022-35949: 1.93% estimated exploitation activity in the next 30 days; percentile 79.98 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact undici is vulnerable to SSRF (Server-side Request Forgery) when an application takes in user input into the path/pathname option of undici.request. If a user specifies a URL such as http://127.0.0.1 or //127.0.0.1 Instead of processing the request as http://example.org//127.0.0.1 (or http://example.org/http://127.0.0.1 when http://127.0.0.1 is used), it actually processes the request as http://127.0.0.1/ and sends it to http://127.0.0.1. If a developer passes in user input into path parameter of undici.request, it can result in an SSRF as they will assume that the hostname cannot change, when in actual fact it can change because the specified path parameter is combined with the base URL. Patches This issue was fixed in undici@5.8.1. Workarounds The best workaround is to validate user input before passing it to the undici.request call. For more information If you have any questions or comments about this advisory: - Open an issue in undici repository - To make a report, follow…

Published by the source

18 Aug 2022, 18:59 UTC

Last modified by the source

8 Nov 2023, 04:09 UTC

Source last checked

26 Oct 2026, 12:21 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-8qr4-xgw6-wmr3

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-8qr4-xgw6-wmr3

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# Patch Next advisory brief: CVE-2022-35949

Advisory: `undici.request` vulnerable to SSRF using absolute URL on `pathname`
IDs: CVE-2022-35949, GHSA-8qr4-xgw6-wmr3
Record: https://patchnext.com/advisories/cve-2022-35949 (revision 2, source checked 26 Oct 2026, 12:21 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: undici 5.8.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm undici: affected <= 5.8.1; fixed in 5.8.2

## Suggested inspection (read-only)
- `npm ls undici --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on undici.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-8qr4-xgw6-wmr3 (OSV record GHSA-8qr4-xgw6-wmr3 lists affected ranges: npm undici >=0 <5.8.2 (fixed))
- Verified: https://github.com/advisories/GHSA-8qr4-xgw6-wmr3 (GitHub-reviewed advisory GHSA-8qr4-xgw6-wmr3 lists affected ranges: npm undici >=0 <=5.8.1)

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