Vulnerability-Lookup

CVE-2026-9487 (GCVE-0-2026-9487)

Vulnerability from cvelistv5 – Published: 2026-08-03 13:14 – Updated: 2026-08-03 19:59

Title

XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID

Summary

XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID. _get_signed_xml() in lib/XML/Sig.pm, called from verify(), resolves the SignedInfo Reference/@URI to a node with the XPath expression "//*[@ID='$id']" and returns the first node of the resulting node set. A document in which two elements share that ID value is accepted: the digest and signature are checked against whichever element comes first in document order, and the duplicate is not detected. Such a document verifies successfully while an application that resolves the same ID independently can read the second, attacker supplied element; in a SAML2 context this places the contents of an Assertion under attacker control.

Severity

9.1 (Critical)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-347 - Improper Verification of Cryptographic Signature

Assigner

CPANSec

References

2 references

URL	Tags
https://github.com/perl-net-saml2/perl-XML-Sig/co…	patch
https://metacpan.org/release/TIMLEGGE/XML-Sig-0.7…	release-notes

Impacted products

1 product

Vendor	Product	Version
TIMLEGGE	XML::Sig	Affected: 0 , < 0.71 (custom)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 9.1,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-9487",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-03T19:59:25.051641Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-03T19:59:47.580Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://cpan.org/modules",
          "defaultStatus": "unaffected",
          "packageName": "XML-Sig",
          "product": "XML::Sig",
          "programFiles": [
            "lib/XML/Sig.pm"
          ],
          "programRoutines": [
            {
              "name": "XML::Sig::verify"
            },
            {
              "name": "XML::Sig::_get_signed_xml"
            }
          ],
          "repo": "https://github.com/perl-net-saml2/perl-XML-Sig",
          "vendor": "TIMLEGGE",
          "versions": [
            {
              "lessThan": "0.71",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID.\n\n_get_signed_xml() in lib/XML/Sig.pm, called from verify(), resolves the SignedInfo Reference/@URI to a node with the XPath expression \"//*[@ID=\u0027$id\u0027]\" and returns the first node of the resulting node set. A document in which two elements share that ID value is accepted: the digest and signature are checked against whichever element comes first in document order, and the duplicate is not detected.\n\nSuch a document verifies successfully while an application that resolves the same ID independently can read the second, attacker supplied element; in a SAML2 context this places the contents of an Assertion under attacker control."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-347",
              "description": "CWE-347 Improper Verification of Cryptographic Signature",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-03T13:14:43.135Z",
        "orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
        "shortName": "CPANSec"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/perl-net-saml2/perl-XML-Sig/commit/4976bde5245df69b8e02c6ae061acbd4891cd7f9.patch"
        },
        {
          "tags": [
            "release-notes"
          ],
          "url": "https://metacpan.org/release/TIMLEGGE/XML-Sig-0.71/source/Changes"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Upgrade to version 0.71"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID",
      "workarounds": [
        {
          "lang": "en",
          "value": "Signing the outermost \u003csamlp:Response\u003e element rather than only the inner \u003csaml:Assertion\u003e reduces exposure, but does not prevent wrapping variants in which the duplicate ID is introduced outside the signed element. Upgrading to 0.71 is the complete fix."
        }
      ],
      "x_generator": {
        "engine": "cpansec-cna-tool 0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e",
    "assignerShortName": "CPANSec",
    "cveId": "CVE-2026-9487",
    "datePublished": "2026-08-03T13:14:43.135Z",
    "dateReserved": "2026-05-24T13:47:37.954Z",
    "dateUpdated": "2026-08-03T19:59:47.580Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-9487",
      "date": "2026-08-04",
      "epss": "0.00167",
      "percentile": "0.06318"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-9487\",\"sourceIdentifier\":\"9b29abf9-4ab0-4765-b253-1875cd9b441e\",\"published\":\"2026-08-03T14:16:31.110\",\"lastModified\":\"2026-08-03T20:17:30.720\",\"vulnStatus\":\"Undergoing Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID.\\n\\n_get_signed_xml() in lib/XML/Sig.pm, called from verify(), resolves the SignedInfo Reference/@URI to a node with the XPath expression \\\"//*[@ID=\u0027$id\u0027]\\\" and returns the first node of the resulting node set. A document in which two elements share that ID value is accepted: the digest and signature are checked against whichever element comes first in document order, and the duplicate is not detected.\\n\\nSuch a document verifies successfully while an application that resolves the same ID independently can read the second, attacker supplied element; in a SAML2 context this places the contents of an Assertion under attacker control.\"}],\"affected\":[{\"source\":\"9b29abf9-4ab0-4765-b253-1875cd9b441e\",\"affectedData\":[{\"vendor\":\"TIMLEGGE\",\"product\":\"XML::Sig\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://cpan.org/modules\",\"packageName\":\"XML-Sig\",\"programFiles\":[\"lib/XML/Sig.pm\"],\"programRoutines\":[{\"name\":\"XML::Sig::verify\"},{\"name\":\"XML::Sig::_get_signed_xml\"}],\"repo\":\"https://github.com/perl-net-saml2/perl-XML-Sig\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"0.71\",\"versionType\":\"custom\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N\",\"baseScore\":9.1,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":5.2}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-08-03T19:59:25.051641Z\",\"id\":\"CVE-2026-9487\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"yes\"},{\"technicalImpact\":\"total\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"9b29abf9-4ab0-4765-b253-1875cd9b441e\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-347\"}]}],\"references\":[{\"url\":\"https://github.com/perl-net-saml2/perl-XML-Sig/commit/4976bde5245df69b8e02c6ae061acbd4891cd7f9.patch\",\"source\":\"9b29abf9-4ab0-4765-b253-1875cd9b441e\"},{\"url\":\"https://metacpan.org/release/TIMLEGGE/XML-Sig-0.71/source/Changes\",\"source\":\"9b29abf9-4ab0-4765-b253-1875cd9b441e\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 9.1, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-9487\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-03T19:59:25.051641Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-03T19:59:42.866Z\"}}], \"cna\": {\"title\": \"XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID\", \"source\": {\"discovery\": \"UNKNOWN\"}, \"affected\": [{\"repo\": \"https://github.com/perl-net-saml2/perl-XML-Sig\", \"vendor\": \"TIMLEGGE\", \"product\": \"XML::Sig\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"0.71\", \"versionType\": \"custom\"}], \"packageName\": \"XML-Sig\", \"programFiles\": [\"lib/XML/Sig.pm\"], \"collectionURL\": \"https://cpan.org/modules\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"XML::Sig::verify\"}, {\"name\": \"XML::Sig::_get_signed_xml\"}]}], \"solutions\": [{\"lang\": \"en\", \"value\": \"Upgrade to version 0.71\"}], \"references\": [{\"url\": \"https://github.com/perl-net-saml2/perl-XML-Sig/commit/4976bde5245df69b8e02c6ae061acbd4891cd7f9.patch\", \"tags\": [\"patch\"]}, {\"url\": \"https://metacpan.org/release/TIMLEGGE/XML-Sig-0.71/source/Changes\", \"tags\": [\"release-notes\"]}], \"workarounds\": [{\"lang\": \"en\", \"value\": \"Signing the outermost \u003csamlp:Response\u003e element rather than only the inner \u003csaml:Assertion\u003e reduces exposure, but does not prevent wrapping variants in which the duplicate ID is introduced outside the signed element. Upgrading to 0.71 is the complete fix.\"}], \"x_generator\": {\"engine\": \"cpansec-cna-tool 0.1\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID.\\n\\n_get_signed_xml() in lib/XML/Sig.pm, called from verify(), resolves the SignedInfo Reference/@URI to a node with the XPath expression \\\"//*[@ID=\u0027$id\u0027]\\\" and returns the first node of the resulting node set. A document in which two elements share that ID value is accepted: the digest and signature are checked against whichever element comes first in document order, and the duplicate is not detected.\\n\\nSuch a document verifies successfully while an application that resolves the same ID independently can read the second, attacker supplied element; in a SAML2 context this places the contents of an Assertion under attacker control.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-347\", \"description\": \"CWE-347 Improper Verification of Cryptographic Signature\"}]}], \"providerMetadata\": {\"orgId\": \"9b29abf9-4ab0-4765-b253-1875cd9b441e\", \"shortName\": \"CPANSec\", \"dateUpdated\": \"2026-08-03T13:14:43.135Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-9487\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-03T19:59:47.580Z\", \"dateReserved\": \"2026-05-24T13:47:37.954Z\", \"assignerOrgId\": \"9b29abf9-4ab0-4765-b253-1875cd9b441e\", \"datePublished\": \"2026-08-03T13:14:43.135Z\", \"assignerShortName\": \"CPANSec\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

GHSA-WQP7-2WW4-Q6MF

Vulnerability from github – Published: 2026-08-03 15:32 – Updated: 2026-08-03 21:31

Details

XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID.

_get_signed_xml() in lib/XML/Sig.pm, called from verify(), resolves the SignedInfo Reference/@URI to a node with the XPath expression "//*[@ID='$id']" and returns the first node of the resulting node set. A document in which two elements share that ID value is accepted: the digest and signature are checked against whichever element comes first in document order, and the duplicate is not detected.

Such a document verifies successfully while an application that resolves the same ID independently can read the second, attacker supplied element; in a SAML2 context this places the contents of an Assertion under attacker control.

Severity

9.1 (Critical)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-9487"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-347"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-03T14:16:31Z",
    "severity": "CRITICAL"
  },
  "details": "XML::Sig versions before 0.71 for Perl allow signature wrapping via duplicate ID.\n\n_get_signed_xml() in lib/XML/Sig.pm, called from verify(), resolves the SignedInfo Reference/@URI to a node with the XPath expression \"//*[@ID=\u0027$id\u0027]\" and returns the first node of the resulting node set. A document in which two elements share that ID value is accepted: the digest and signature are checked against whichever element comes first in document order, and the duplicate is not detected.\n\nSuch a document verifies successfully while an application that resolves the same ID independently can read the second, attacker supplied element; in a SAML2 context this places the contents of an Assertion under attacker control.",
  "id": "GHSA-wqp7-2ww4-q6mf",
  "modified": "2026-08-03T21:31:35Z",
  "published": "2026-08-03T15:32:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9487"
    },
    {
      "type": "WEB",
      "url": "https://github.com/perl-net-saml2/perl-XML-Sig/commit/4976bde5245df69b8e02c6ae061acbd4891cd7f9.patch"
    },
    {
      "type": "WEB",
      "url": "https://metacpan.org/release/TIMLEGGE/XML-Sig-0.71/source/Changes"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

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.

Action not permitted

CVE-2026-9487 (GCVE-0-2026-9487)

GHSA-WQP7-2WW4-Q6MF

Tags

Sightings

Nomenclature