Pocket ID: Open Redirect on the OIDC /authorize page via unvalidated redirect_uri with prompt=none (CVE-2026-55834) | HOL Guard CVE

Medium · CVSS 4.3CVE-2026-55834GHSA-2WVM-8MVP-22QV

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

Answer in brief

CVE-2026-55834 records a Medium severity (CVSS 4.3) vulnerability in Pocket ID: Open Redirect on the OIDC /authorize page via unvalidated redirect_uri with prompt=none. The current sources do not mark it as known exploited. The current feed maps pocket-id/pocket-id (generic), github.com/pocket-id/pocket-id/backend (go). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 28, 2026Updated Aug 28, 2026Source checked Aug 28, 2026First seen by HOL Aug 28, 2026Material review Aug 28, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.3
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 4.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps pocket-id/pocket-id (generic), github.com/pocket-id/pocket-id/backend (go). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
pocket-id/pocket-idgeneric	>= 2.6.0, < 2.9.0	Not reported
github.com/pocket-id/pocket-id/backendgo	>=2.6.0,<=2.8.0	2.9.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for pocket-id/pocket-id, github.com/pocket-id/pocket-id/backend.
Review the reported fix. Update github.com/pocket-id/pocket-id/backend to 2.9.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 28, 2026

Sources and claim methodology

Upstream source description

Pocket ID is an OIDC provider that allows users to authenticate with their passkeys to services. From 2.6.0 until 2.9.0, frontend/src/routes/authorize/+page.ts reads the redirect_uri query parameter and frontend/src/routes/authorize/+page.svelte uses the raw callbackURL in redirectWithError when prompt=none cannot complete silent authorization. The client-side path only blocks javascript and data schemes and does not invoke the backend callback allow-list validation, so an unauthenticated attacker who knows a valid client_id can redirect a victim browser to an arbitrary HTTP or HTTPS origin for phishing or OIDC error and state smuggling. This issue is fixed in version 2.9.0.

Quoted source text, attributed separately from HOL analysis.