SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-55834

Pocket ID is an OIDC provider that allows users to authenticate with their passkeys to services.

MEDIUM 4.3EPSS 0.27%

Does this matter?

Lower severity and a low EPSS score (0.27%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1
4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
EPSS
0.27% probability · 19th percentile
CISA KEV
Not listed
Weakness
CWE-601
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.