Quick answers
- Is CVE-2026-55834 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-55834 being exploited in the wild.
- How severe is CVE-2026-55834?
- Medium severity, with a CVSS score of 4.3, published 28 August 2026.
- Which products and versions are affected?
- github.com/pocket-id/pocket-id/backend (Go) >= 2.6.0, <= 2.8.0, SEMVER:introduced=0, SEMVER:introduced=2.6.0,fixed=2.9.0.
- Is there a fix for CVE-2026-55834?
- Yes. github.com/pocket-id/pocket-id/backend (Go): upgrade to 2.9.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-55834 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-55834?
- Check whether you run github.com/pocket-id/pocket-id/backend (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- github.com/pocket-id/pocket-id/backend (Go): upgrade to 2.9.0 or later
go get github.com/pocket-id/pocket-id/backend@v2.9.0
Technical details
This is an open redirect vulnerability (CWE-601) in the OIDC /authorize endpoint of Pocket-ID's SvelteKit frontend. The vulnerability occurs when an authorization request includes prompt=none and the user cannot be silently authenticated. The frontend at frontend/src/routes/authorize/+page.svelte parses the redirect_uri query parameter and directly uses it in a window.location.href redirect without consulting the backend's GetCallbackURLFromList validator, which enforces a per-client allow-list of valid redirect URLs. While basic URL scheme filtering (blocking javascript: and data: URLs) is applied, any http: or https: origin passes through. An unauthenticated attacker with knowledge of a client_id (obtainable from public metadata endpoints) can craft an authorization URL that redirects victims to attacker-controlled endpoints, enabling phishing and OAuth response parameter leakage. The standard interactive flow (without prompt=none) correctly validates against the backend allow-list before redirecting. A second attack variant exists when an authenticated victim attempts first-time authorization of a client. The fix is available in version 2.9.0.
Affected products
- Pocket-ID Pocket-ID >= 2.6.0, <= 2.8.0
Identifiers
- CVE-2026-55834
- GHSA-2wvm-8mvp-22qv
- GO-2026-6305
Timeline
- 2026-08-28: disclosed: Vulnerability published to GitHub Advisory Database
- 2026-06-16: patched: Patch released in version 2.9.0