CVE-2026-28512: Pocket ID OAuth Redirect_uri Validation Bypass Vulnerability

HIGH
Advisory Identifier: GHSA-9h33-g3ww-mqff
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CVSS 7.1
CWE-601
Published
Advisory Summary

CVE-2026-28512 is a HIGH (CVSS 7.1) oauth redirect_uri validation bypass vulnerability (CWE-601: URL Redirection to Untrusted Site ('Open Redirect')) affecting Pocket ID libraries in the Go ecosystem. The issue involves oauth redirect_uri validation bypass via userinfo/host confusion. Remediation is available by upgrading affected packages to version 0.0.0-20260228130835-3a339e33191c.

CVE-2026-28512 at a Glance

CVE Identifier CVE-2026-28512
GHSA Identifier GHSA-9h33-g3ww-mqff
Severity HIGH
CVSS v3.1 Base Score 7.1
CWE Classification CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
Affected Product Pocket ID
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 7.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction Required (UI:R)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2026-28512

To remediate this vulnerability, upgrade all affected Pocket ID dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/pocket-id/pocket-id/backend fixed: 0.0.0-20260228130835-3a339e33191c 
Upgrade github.com/pocket-id/pocket-id/backend to 0.0.0-20260228130835-3a339e33191c
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for github.com/pocket-id/pocket-id/backend

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-28512, inspect your project dependencies for Pocket ID:

inspect dependencies for github.com/pocket-id/pocket-id/backend

Analyze the terminal output to locate any version of Pocket ID in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.0.0-20260228130835-3a339e33191c), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-601: URL Redirection to Untrusted Site ('Open Redirect'), where the web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect. In Pocket ID, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact A flaw in callback URL validation allowed crafted `redirect_uri` values containing URL userinfo (`@`) to bypass legitimate callback pattern checks. If an attacker can trick a user into opening a malicious authorization link, the authorization code may be redirected to an attacker-controlled host. ### Patches Fixed in `v2.3.1` (commit 3a339e33191c31b68bf57db907f800d9de5ffbc8). The fix replaces delimiter-based callback matching with structured URL pattern matching and updates validation logic/tests. ### Workarounds - Reject callback URLs containing userinfo (`@`) at reverse proxy / app policy level if feasible.

CVE-2026-28512 Affected Pocket ID Versions

1 component(s)
Fixed Versions:
0.0.0-20260228130835-3a339e33191c
Product / Package Ecosystem Affected Versions Fixed Version
github.com/pocket-id/pocket-id/backend
golang/github.com/pocket-id/pocket-id/backend
Go
< 0.0.0-20260228130835-3a339e33191c
0.0.0-20260228130835-3a339e33191c

References

GitHub Advisory / Wiki ADVISORY
https://github.com/pocket-id/pocket-id/security/advisories/GHSA-9h33-g3ww-mqff
NVD — CVE-2026-28512 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-28512
Security Fix Commit FIX COMMIT
https://github.com/pocket-id/pocket-id/commit/3a339e33191c31b68bf57db907f800d9de5ffbc8
Pocket ID Source Repository REPOSITORY
https://github.com/pocket-id/pocket-id

Frequently Asked Questions

What is CVE-2026-28512?
CVE-2026-28512 is a security vulnerability in Pocket ID involving OAuth redirect_uri validation bypass via userinfo/host confusion under CWE-601: URL Redirection to Untrusted Site ('Open Redirect').
Which Pocket ID versions are affected?
Affected versions include releases prior to 0.0.0-20260228130835-3a339e33191c across affected packages: github.com/pocket-id/pocket-id/backend.
What version fixes CVE-2026-28512?
Upgrading to 0.0.0-20260228130835-3a339e33191c (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/pocket-id/pocket-id/backend affected?
Yes, github.com/pocket-id/pocket-id/backend is affected in releases prior to 0.0.0-20260228130835-3a339e33191c. Upgrade your dependency to 0.0.0-20260228130835-3a339e33191c or later.
What is the CVSS score of CVE-2026-28512?
CVE-2026-28512 has a CVSS v3.1 base score of 7.1 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N.
What CWE is associated with CVE-2026-28512?
CVE-2026-28512 is classified under CWE-601: URL Redirection to Untrusted Site ('Open Redirect') (The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.).
How can I check Go dependencies for CVE-2026-28512?
Run the dependency tree command: 'inspect dependencies for github.com/pocket-id/pocket-id/backend'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-9h33-g3ww-mqff",
  "modified" : "2026-03-10T18:43:02Z",
  "published" : "2026-03-09T17:24:27Z",
  "aliases" : [ "CVE-2026-28512" ],
  "summary" : "Pocket ID: OAuth redirect_uri validation bypass via userinfo/host confusion",
  "details" : "### Impact\nA flaw in callback URL validation allowed crafted `redirect_uri` values containing URL userinfo (`@`) to bypass legitimate callback pattern checks. If an attacker can trick a user into opening a malicious authorization link, the authorization code may be redirected to an attacker-controlled host.\n\n### Patches\nFixed in `v2.3.1` (commit 3a339e33191c31b68bf57db907f800d9de5ffbc8).\nThe fix replaces delimiter-based callback matching with structured URL pattern matching and updates validation logic/tests.\n\n### Workarounds\n- Reject callback URLs containing userinfo (`@`) at reverse proxy / app policy level if feasible.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/pocket-id/pocket-id/backend"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.0.0-20260228130835-3a339e33191c"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/pocket-id/pocket-id/security/advisories/GHSA-9h33-g3ww-mqff"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-28512"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pocket-id/pocket-id/commit/3a339e33191c31b68bf57db907f800d9de5ffbc8"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/pocket-id/pocket-id"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-601" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-09T17:24:27Z",
    "nvd_published_at" : "2026-03-10T17:38:50Z"
  }
}