Vulnerability-Lookup

GHSA-3H23-RRPC-3P87

Vulnerability from github – Published: 2026-05-19 20:29 – Updated: 2026-05-19 20:29

Summary

Caddy Defender trusted proxy client IP bypass

Details

Impact

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.

Patches

The issue is fixed 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.

Users should upgrade to v0.10.1 or later.

Workarounds

There is no complete workaround in affected Defender versions for deployments that rely on Caddys 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 clients, without an intermediate trusted proxy, are not affected by this bypass.

Severity

8.2 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "pkg.jsn.cam/caddy-defender"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.10.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-46415"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-284",
      "CWE-348"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-19T20:29:14Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Impact\n\nCaddy Defender used `r.RemoteAddr` when evaluating whether a request should be blocked. `RemoteAddr` is the address of the immediate peer connected to Caddy.\n\nIn 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.\n\nAs 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.\n\n### Patches\n\nThe issue is fixed 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.\n\nUsers should upgrade to `v0.10.1` or later.\n\n### Workarounds\n\nThere is no complete workaround in affected Defender versions for deployments that rely on Caddys trusted proxy client IP resolution.\n\nUntil upgrading, affected users should enforce equivalent IP blocking at the trusted proxy, CDN, load balancer, firewall, or other edge layer before traffic reaches Caddy.\n\nDeployments where Caddy receives traffic directly from clients, without an intermediate trusted proxy, are not affected by this bypass.",
  "id": "GHSA-3h23-rrpc-3p87",
  "modified": "2026-05-19T20:29:14Z",
  "published": "2026-05-19T20:29:14Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/JasonLovesDoggo/caddy-defender/security/advisories/GHSA-3h23-rrpc-3p87"
    },
    {
      "type": "WEB",
      "url": "https://github.com/JasonLovesDoggo/caddy-defender/pull/139"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/JasonLovesDoggo/caddy-defender"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Caddy Defender trusted proxy client IP bypass"
}

CVE-2026-46415 (GCVE-0-2026-46415)

Vulnerability from cvelistv5 – Published: 2026-07-20 15:05 – Updated: 2026-07-21 13:53

Title

Caddy Defender trusted proxy client IP bypass

Summary

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 clients, without an intermediate trusted proxy, are not affected by this bypass.

Severity

8.2 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-21 13:52 UTC

CWE

CWE-284 - Improper Access Control
CWE-348 - Use of Less Trusted Source

Assigner

GitHub_M CNA under the mitre root

CNA scorecard C 72/100 over 7814 records in the last 180 days details

References

4 references

URL	Tags
https://github.com/JasonLovesDoggo/caddy-defender…	x_refsource_CONFIRM
https://github.com/JasonLovesDoggo/caddy-defender…	x_refsource_MISC
https://caddyserver.com/docs/caddyfile/matchers#c…	x_refsource_MISC
https://caddyserver.com/docs/caddyfile/options#tr…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
JasonLovesDoggo	caddy-defender	Affected: < 0.10.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-46415",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-21T13:52:55.935258Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-21T13:53:08.959Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "caddy-defender",
          "vendor": "JasonLovesDoggo",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.10.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The Caddy Defender plugin is a middleware for Caddy that allows users to block or manipulate requests based on the client\u0027s 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\u0027s 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 clients, without an intermediate trusted proxy, are not affected by this bypass."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 8.2,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-284",
              "description": "CWE-284: Improper Access Control",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-348",
              "description": "CWE-348: Use of Less Trusted Source",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-20T15:05:21.961Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/JasonLovesDoggo/caddy-defender/security/advisories/GHSA-3h23-rrpc-3p87",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/JasonLovesDoggo/caddy-defender/security/advisories/GHSA-3h23-rrpc-3p87"
        },
        {
          "name": "https://github.com/JasonLovesDoggo/caddy-defender/pull/139",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/JasonLovesDoggo/caddy-defender/pull/139"
        },
        {
          "name": "https://caddyserver.com/docs/caddyfile/matchers#client-ip",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://caddyserver.com/docs/caddyfile/matchers#client-ip"
        },
        {
          "name": "https://caddyserver.com/docs/caddyfile/options#trusted-proxies",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://caddyserver.com/docs/caddyfile/options#trusted-proxies"
        }
      ],
      "source": {
        "advisory": "GHSA-3h23-rrpc-3p87",
        "discovery": "UNKNOWN"
      },
      "title": "Caddy Defender trusted proxy client IP bypass"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-46415",
    "datePublished": "2026-07-20T15:05:21.961Z",
    "dateReserved": "2026-05-13T21:04:10.933Z",
    "dateUpdated": "2026-07-21T13:53:08.959Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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