Vulnerability-Lookup

GHSA-V6G5-XXRX-M495

Vulnerability from github – Published: 2026-08-20 03:32 – Updated: 2026-08-28 18:31

Details

Punk::OAuth2 versions before 0.03 for Perl allow an attacker-chosen off-site redirect after login because same_origin_path accepts a backslash or tab in the return parameter.

oauth2_login reads the return parameter from the initiation request, runs same_origin_path over it, and stores the survivor in the session flow record as the post-login redirect target. That check rejects a value that does not begin with a slash, one with a slash as its second byte, and one containing CR or LF. A backslash and a tab pass. The URL Standard treats a backslash as equivalent to a slash for special schemes, so /\evil.example parses with the authority evil.example. It also strips ASCII tab before parsing, so a tab between two leading slashes leaves //evil.example.

A crafted link to the application's own login route lands the victim on the attacker's site after a genuine authentication. The redirect carries no authorization code or access token.

Severity

5.7 (Medium)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-75628"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-601"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-20T01:16:53Z",
    "severity": "MODERATE"
  },
  "details": "Punk::OAuth2 versions before 0.03 for Perl allow an attacker-chosen off-site redirect after login because same_origin_path accepts a backslash or tab in the return parameter.\n\noauth2_login reads the return parameter from the initiation request, runs same_origin_path over it, and stores the survivor in the session flow record as the post-login redirect target. That check rejects a value that does not begin with a slash, one with a slash as its second byte, and one containing CR or LF. A backslash and a tab pass. The URL Standard treats a backslash as equivalent to a slash for special schemes, so `/\\evil.example` parses with the authority `evil.example`. It also strips ASCII tab before parsing, so a tab between two leading slashes leaves `//evil.example`.\n\nA crafted link to the application\u0027s own login route lands the victim on the attacker\u0027s site after a genuine authentication. The redirect carries no authorization code or access token.",
  "id": "GHSA-v6g5-xxrx-m495",
  "modified": "2026-08-28T18:31:22Z",
  "published": "2026-08-20T03:32:54Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-75628"
    },
    {
      "type": "WEB",
      "url": "https://datatracker.ietf.org/doc/html/rfc9700#section-4.11.1"
    },
    {
      "type": "WEB",
      "url": "https://metacpan.org/release/LNATION/Punk-OAuth2-0.02/source/include/pox/pox_util.h#L94"
    },
    {
      "type": "WEB",
      "url": "https://metacpan.org/release/LNATION/Punk-OAuth2-0.03/changes"
    },
    {
      "type": "WEB",
      "url": "https://url.spec.whatwg.org/#concept-basic-url-parser"
    },
    {
      "type": "WEB",
      "url": "https://url.spec.whatwg.org/#relative-slash-state"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/08/20/1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-75628 (GCVE-0-2026-75628)

Vulnerability from cvelistv5 – Published: 2026-08-20 00:40 – Updated: 2026-08-28 15:11

Title

Punk::OAuth2 versions before 0.03 for Perl allow an attacker-chosen off-site redirect after login because same_origin_path accepts a backslash or tab in the return parameter

Summary

Punk::OAuth2 versions before 0.03 for Perl allow an attacker-chosen off-site redirect after login because same_origin_path accepts a backslash or tab in the return parameter. oauth2_login reads the return parameter from the initiation request, runs same_origin_path over it, and stores the survivor in the session flow record as the post-login redirect target. That check rejects a value that does not begin with a slash, one with a slash as its second byte, and one containing CR or LF. A backslash and a tab pass. The URL Standard treats a backslash as equivalent to a slash for special schemes, so `/\evil.example` parses with the authority `evil.example`. It also strips ASCII tab before parsing, so a tab between two leading slashes leaves `//evil.example`. A crafted link to the application's own login route lands the victim on the attacker's site after a genuine authentication. The redirect carries no authorization code or access token.

Severity

5.7 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-28 15:11 UTC

CWE

CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')

Assigner

CPANSec redhat root

References

6 references

URL	Tags
https://metacpan.org/release/LNATION/Punk-OAuth2-…	release-notes
https://metacpan.org/release/LNATION/Punk-OAuth2-…	technical-description
https://datatracker.ietf.org/doc/html/rfc9700#sec…	technical-description
https://url.spec.whatwg.org/#relative-slash-state	technical-description
https://url.spec.whatwg.org/#concept-basic-url-parser	technical-description
http://www.openwall.com/lists/oss-security/2026/08/20/1

Impacted products

1 product

Vendor	Product	Version
		Affected: 0 , < 0.03 (custom)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2026-08-20T02:25:36.019Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/08/20/1"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 5.7,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "REQUIRED",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-75628",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-28T15:11:05.001417Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-28T15:11:53.961Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://cpan.org/modules",
          "defaultStatus": "unaffected",
          "modules": [
            "Punk::OAuth2"
          ],
          "packageName": "Punk-OAuth2",
          "packageURL": "pkg:cpan/Punk-OAuth2",
          "programFiles": [
            "include/pox/pox_util.h",
            "lib/Punk/Plugin/OAuth2.pm"
          ],
          "programRoutines": [
            {
              "name": "Punk::OAuth2::same_origin_path"
            }
          ],
          "versions": [
            {
              "lessThan": "0.03",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Punk::OAuth2 versions before 0.03 for Perl allow an attacker-chosen off-site redirect after login because same_origin_path accepts a backslash or tab in the return parameter.\n\noauth2_login reads the return parameter from the initiation request, runs same_origin_path over it, and stores the survivor in the session flow record as the post-login redirect target. That check rejects a value that does not begin with a slash, one with a slash as its second byte, and one containing CR or LF. A backslash and a tab pass. The URL Standard treats a backslash as equivalent to a slash for special schemes, so `/\\evil.example` parses with the authority `evil.example`. It also strips ASCII tab before parsing, so a tab between two leading slashes leaves `//evil.example`.\n\nA crafted link to the application\u0027s own login route lands the victim on the attacker\u0027s site after a genuine authentication. The redirect carries no authorization code or access token."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-601",
              "description": "CWE-601 URL Redirection to Untrusted Site (\u0027Open Redirect\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-20T00:40:08.220Z",
        "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "shortName": "CPANSec"
      },
      "references": [
        {
          "tags": [
            "release-notes"
          ],
          "url": "https://metacpan.org/release/LNATION/Punk-OAuth2-0.03/changes"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://metacpan.org/release/LNATION/Punk-OAuth2-0.02/source/include/pox/pox_util.h#L94"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://datatracker.ietf.org/doc/html/rfc9700#section-4.11.1"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://url.spec.whatwg.org/#relative-slash-state"
        },
        {
          "tags": [
            "technical-description"
          ],
          "url": "https://url.spec.whatwg.org/#concept-basic-url-parser"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to Punk-OAuth2 0.03 or later."
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Punk::OAuth2 versions before 0.03 for Perl allow an attacker-chosen off-site redirect after login because same_origin_path accepts a backslash or tab in the return parameter",
      "workarounds": [
        {
          "lang": "en",
          "value": "For deployments that cannot upgrade to 0.03, strip the return query parameter from requests to the oauth2_login initiation route at the reverse proxy. Logins then use the configured redirect_ok destination."
        }
      ],
      "x_generator": {
        "engine": "cpansec-cna-tool 0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
    "assignerShortName": "CPANSec",
    "cveId": "CVE-2026-75628",
    "datePublished": "2026-08-20T00:40:08.220Z",
    "dateReserved": "2026-08-18T01:18:00.649Z",
    "dateUpdated": "2026-08-28T15:11:53.961Z",
    "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.

Detection rules are retrieved from Rulezet.

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

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