Categories
CVE-2026-62367

Authentication Bypass in code.vikunja.io/api (CVE-2026-62367)

Summary

Authentication bypass in code.vikunja.io/api (CVE-2026-62367). Risk of unauthorized operations or information disclosure. Exploitable via emailfallback. Mitigation: upgrade to 2.4.0 or later.

Original description

The description as published by the source.

Summary

With the per-provider OIDC emailfallback option enabled, Vikunja links an SSO login to a pre-existing local (username+password) account using only the email claim — no email_verified (or Microsoft xms_edov) check and no password check, on the unauthenticated callback. An attacker who can make the configured issuer emit a token bearing a victim's email logs in as that victim with a full session and no victim interaction (the nOAuth / Grafana CVE-2023-3128 class). The 2.3.0 fix for GHSA-8jvc-mcx6-r4cg added a TOTP gate, not an email_verified gate, so users without TOTP remain exposed.

Details

References are pkg/modules/auth/openid/openid.go at HEAD. Identity is first resolved on the immutable (issuer, subject) pair (openid.go:428). On a subject miss with emailfallback on, fallbackSearchUsers adds an email-only lookup against local accounts:

// openid.go:413
searches = append(searches, &user.User{Issuer: user.IssuerLocal, Email: cl.Email})

getUser resolves this via s.Get(), which ANDs non-zero fields -> WHERE issuer='local' AND email=?. Local users always have Issuer="local" (user_create.go:38), so the lookup matches any local account by email alone; getOrCreateUser returns it and the caller mints a session — the password is never read. The claims struct has no email_verified field (openid.go:80) and getClaims never consults one; a repo-wide grep for email_verified/xms_edov returns nothing. The code alr…

Source: GitHub Security Advisories (Global) NVD GitHub Advisory

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2026-62367 has been found in code.vikunja.io/api.
Attackers can target a specific entry point like emailfallback over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade code.vikunja.io/api to 2.4.0 or later.
If unsure, ask your IT team or search "code.vikunja.io/api CVE-2026-62367" on the vendor's site.

CVE-2026-62367 (code.vikunja.io/api) — CWE-287
Attack surface: emailfallback / email / email_verified / xms_edov
Patched: 2.4.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

Authentication bypass (CWE-287) exists in code.vikunja.io/api. Attackers reach the vulnerable code path via emailfallback.

📍 Affected scope

Check the vendor advisory for the affected versions of code.vikunja.io/api. Attack surface: emailfallback / email / email_verified / xms_edov.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 2.4.0.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'code.vikunja.io/api' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

  1. 1
    Identify exposure identify
    grep -r 'code.vikunja.io/api' . | grep -v node_modules

    リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で code.vikunja.io/api を grep し、稼働しているサービス・バージョンを把握する。

  2. 2
    Apply patch patch
    Upgrade code.vikunja.io/api to 2.4.0

    ステージング環境で 2.4.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。

  3. 3
    Post-deployment verification verify
    Confirm patched version is live in production

    パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

go code.vikunja.io/api
[{"type":"SEMVER","events":[{"introduced":"1.0.0"},{"fixed":"2.4.0"}]}]

References

We use cookies for analytics and ad measurement. This setting applies to all Game co., Ltd. sites. Details