Pocket-ID has an Open Redirect on the OIDC /authorize page via unvalidated redirect_uri with prompt=none

Exploitation

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

CVSS

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

EPSS

• CVE-2026-55834: 0.37% estimated exploitation activity in the next 30 days; percentile 31.36 (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.

Summary The OIDC authorization page in the pocket-id frontend redirects the browser to an attacker-controlled URL without consulting the backend redirecturi allow-list when the request uses prompt=none. An attacker who knows a valid clientid can craft an /authorize link that sends a victim (or a victim's browser doing a silent re-auth) to any external https URL, enabling phishing and OAuth response smuggling. The backend allow-list validation that protects the normal authenticated flow is bypassed because this path is handled entirely client-side. Details For an OIDC authorization request with prompt=none, the SvelteKit frontend short-circuits the flow before the backend ever validates the redirecturi against the client's registered callback list. File: frontend/src/routes/authorize/+page.ts (line 14) parses the raw redirecturi query parameter from the incoming URL. File: frontend/src/routes/authorize/+page.svelte - in onMount(), when the request carries prompt=none and the user…

Published by the source

28 Aug 2026, 16:28 UTC

Last modified by the source

2 Sep 2026, 19:45 UTC

Source last checked

26 Oct 2026, 15:28 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-2wvm-8mvp-22qv

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6305

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-2wvm-8mvp-22qv

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# Patch Next advisory brief: CVE-2026-55834

Advisory: Pocket-ID has an Open Redirect on the OIDC /authorize page via unvalidated redirect_uri with prompt=none
IDs: CVE-2026-55834, GHSA-2wvm-8mvp-22qv
Record: https://patchnext.com/advisories/cve-2026-55834 (revision 3, source checked 26 Oct 2026, 15:28 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/pocket-id/pocket-id/backend 2.9.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/pocket-id/pocket-id/backend: affected >= 2.6.0, <= 2.8.0; fixed in 2.9.0

## Suggested inspection (read-only)
- Go github.com/pocket-id/pocket-id/backend: check the installed version with your package manager.

## 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 github.com/pocket-id/pocket-id/backend.
- 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-2wvm-8mvp-22qv (OSV record GHSA-2wvm-8mvp-22qv lists affected ranges: Go github.com/pocket-id/pocket-id/backend >=2.6.0 <2.9.0 (fixed))
- Verified: https://osv.dev/vulnerability/GO-2026-6305 (OSV record GO-2026-6305 lists affected ranges: Go github.com/pocket-id/pocket-id/backend >=0)
- Verified: https://github.com/advisories/GHSA-2wvm-8mvp-22qv (GitHub-reviewed advisory GHSA-2wvm-8mvp-22qv lists affected ranges: Go github.com/pocket-id/pocket-id/backend >=2.6.0 <=2.8.0)

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