Vulnerability in pkg.jsn.cam/caddy-defender (CVE-2026-46415)
Summary
Vulnerability in pkg.jsn.cam/caddy-defender (CVE-2026-46415). Confidential information can be exposed externally. Exploitable via r.RemoteAddr. Mitigation: upgrade to 0.10.1 or later.
Original description
The description as published by the source.
The Caddy Defender plugin is a middleware for Caddy that allows users to block or manipulate requests based on the client's IP address. Prior to version 0.10.1, Caddy Defender used r.RemoteAddr when evaluating whether a request should be blocked. RemoteAddr is the address of the immediate peer connected to Caddy. In deployments where Caddy is behind a trusted proxy, CDN, or load balancer, the immediate peer is usually the proxy, not the original client. Caddy resolves the original client address into its client_ip request variable after applying the configured trusted_proxies policy, but Defender did not use that value. As a result, clients from blocked IP ranges could bypass Defender when accessing Caddy through a trusted proxy whose own IP address was not blocked. This affects deployments that use Defender behind trusted proxies and expect it to enforce blocking based on the real client IP. The issue is fixed in version 0.10.1 by making Defender prefer Caddys resolved client_ip request variable when it is available. Defender falls back to RemoteAddr only when Caddy has not provided a resolved client IP. There is no complete workaround in affected Defender versions for deployments that rely on Caddy's trusted proxy client IP resolution. Until upgrading, affected users should enforce equivalent IP blocking at the trusted proxy, CDN, load balancer, firewall, or other edge layer before traffic reaches Caddy. Deployments where Caddy receives traffic directly from cli…
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-2026-46415 has been found in pkg.jsn.cam/caddy-defender.
Attackers can target a specific entry point like r.RemoteAddr over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 8.2/10.
What to do: upgrade pkg.jsn.cam/caddy-defender to 0.10.1 or later.
If unsure, ask your IT team or search "pkg.jsn.cam/caddy-defender CVE-2026-46415" on the vendor's site.
CVE-2026-46415 (pkg.jsn.cam/caddy-defender) — CWE-284 / CVSS v3 8.2
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: r.RemoteAddr / RemoteAddr / client_ip / trusted_proxies
Patched: 0.10.1 — 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-284) exists in pkg.jsn.cam/caddy-defender. Attackers reach the vulnerable code path via r.RemoteAddr without authentication.
Check the vendor advisory for the affected versions of pkg.jsn.cam/caddy-defender. Attack surface: r.RemoteAddr / RemoteAddr / client_ip / trusted_proxies.
Severity: High (CVSS 8.2/10). Confidential information can be exposed externally.
Update to 0.10.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'pkg.jsn.cam/caddy-defender' . 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
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1Identify exposure identify
grep -r 'pkg.jsn.cam/caddy-defender' . | 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
pkg.jsn.cam/caddy-defenderを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade pkg.jsn.cam/caddy-defender to 0.10.1ステージング環境で 0.10.1 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。
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3Post-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
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- patch github.com
- web github.com
- web caddyserver.com
- web caddyserver.com