Open Redirect in github.com/nezhahq/nezha (CVE-2026-53523)
Summary
Vulnerability in github.com/nezhahq/nezha (CVE-2026-53523). Confidential information can be exposed externally. Exploitable via GET /api/v1/oauth2/github. Mitigation: upgrade to 2.2.0 or later.
Original description
The description as published by the source.
1. Description
The getRedirectURL function in oauth2.go:22-29 constructs the OAuth2 callback URL by concatenating the request's Host header with a fixed path, with zero validation of the Host header:
func getRedirectURL(c *gin.Context) string {
scheme := "http://"
referer := c.Request.Referer()
if forwardedProto := c.Request.Header.Get("X-Forwarded-Proto"); forwardedProto == "https" || strings.HasPrefix(referer, "https://") {
scheme = "https://"
}
return scheme + c.Request.Host + "/api/v1/oauth2/callback"
}
File: cmd/dashboard/controller/oauth2.go:22-29
This function is called from oauth2redirect() at line 53:
func oauth2redirect(c *gin.Context) (*model.Oauth2LoginResponse, error) {
// ...
redirectURL := getRedirectURL(c)
o2conf := o2confRaw.Setup(redirectURL)
// ...
url := o2conf.AuthCodeURL(state, oauth2.AccessTypeOnline)
return &model.Oauth2LoginResponse{Redirect: url}, nil
}
The redirectURL is passed into o2confRaw.Setup(redirectURL) which configures the OAuth2 Config.RedirectURL field (oauth2config.go:22-33). This RedirectURL is sent to the OAuth2 provider (e.g., GitHub, Google, Microsoft) as the callback endpoint. The OAuth2 provider will redirect the user's browser — along with the authorization code — to this URL after the user authenticates.
The security issue is that c.Request.Host is directly user-controllable via the HTTP Host header. An attacker who ca…
Source: NIST National Vulnerability Database 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-2026-53523 has been found in github.com/nezhahq/nezha.
Attackers can target a specific entry point like GET /api/v1/oauth2/github over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 6.8/10.
What to do: upgrade github.com/nezhahq/nezha to 2.2.0 or later.
If unsure, ask your IT team or search "github.com/nezhahq/nezha CVE-2026-53523" on the vendor's site.
CVE-2026-53523 (github.com/nezhahq/nezha) — CWE-601 / CVSS v3 6.8
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: GET /api/v1/oauth2/github / Host header / getRedirectURL / Host
Patched: 2.2.0 — 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.
A vulnerability (CWE-601) exists in github.com/nezhahq/nezha. Attackers reach the vulnerable code path via GET /api/v1/oauth2/github without authentication.
Check the vendor advisory for the affected versions of github.com/nezhahq/nezha. Attack surface: GET /api/v1/oauth2/github / Host header / getRedirectURL / Host.
Severity: Medium (CVSS 6.8/10). Confidential information can be exposed externally.
Update to 2.2.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual GET /api/v1/oauth2/github requests with malformed payloads or SQL meta-characters. Run grep -r 'github.com/nezhahq/nezha' . 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
-
1Identify exposure identify
grep -r 'github.com/nezhahq/nezha' . | 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
github.com/nezhahq/nezhaを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'GET /api/v1/oauth2/github' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
GET /api/v1/oauth2/githubへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade github.com/nezhahq/nezha to 2.2.0ステージング環境で 2.2.0 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と、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against GET /api/v1/oauth2/github on staging to confirm patch closes the vector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 Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com