Vulnerability-Lookup

GHSA-45VW-WH46-2VX8

Vulnerability from github – Published: 2026-05-21 21:31 – Updated: 2026-06-05 20:33

Summary

Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation

Details

Description

The obj.(expr) dynamic-attribute syntax (added in 3.15.0 as the replacement for the deprecated attribute() function) lets the attribute be an arbitrary expression. When the receiver is _self (or any {% import %} alias) and the parenthesised expression is a string literal, DotExpressionParser short-circuits to the macro-call path and concatenates the attacker-controlled string into a MacroReferenceExpression name with no identifier validation. MacroReferenceExpression::compile() then emits that name raw into the generated PHP source.

An attacker who can supply template source can inject arbitrary PHP into the compiled template and execute it at template-load time, before checkSecurity() is ever called. This is a complete bypass of SandboxExtension, including a globally-enabled sandbox with an empty SecurityPolicy allowlist.

Resolution

The parser now validates that the dynamic attribute resolves to a valid macro identifier before routing through MacroReferenceExpression, and the macro-reference compiler emits the name through a properly escaped path.

Credits

Twig would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.

Severity

8.7 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

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JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "twig/twig"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.15.0"
            },
            {
              "fixed": "3.26.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-46640"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-94"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-21T21:31:08Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Description\n\nThe `obj.(expr)` dynamic-attribute syntax (added in 3.15.0 as the replacement for the deprecated `attribute()` function) lets the attribute be an arbitrary expression. When the receiver is `_self` (or any `{% import %}` alias) and the parenthesised expression is a string literal, `DotExpressionParser` short-circuits to the macro-call path and concatenates the attacker-controlled string into a `MacroReferenceExpression` name with no identifier validation. `MacroReferenceExpression::compile()` then emits that name raw into the generated PHP source.\n\nAn attacker who can supply template source can inject arbitrary PHP into the compiled template and execute it at template-load time, before `checkSecurity()` is ever called. This is a complete bypass of `SandboxExtension`, including a globally-enabled sandbox with an empty `SecurityPolicy` allowlist.\n\n### Resolution\n\nThe parser now validates that the dynamic attribute resolves to a valid macro identifier before routing through `MacroReferenceExpression`, and the macro-reference compiler emits the name through a properly escaped path.\n\n### Credits\n\nTwig would like to thank Claude Mythos Preview (via Project Glasswing) for reporting the issue and providing the fix.",
  "id": "GHSA-45vw-wh46-2vx8",
  "modified": "2026-06-05T20:33:13Z",
  "published": "2026-05-21T21:31:08Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/twigphp/Twig/security/advisories/GHSA-45vw-wh46-2vx8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/twig/twig/CVE-2026-46640.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/twigphp/Twig"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vladko312/extras/blob/main/CVE-2026-46640.py"
    },
    {
      "type": "WEB",
      "url": "https://symfony.com/cve-2026-46640"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Twig: Arbitrary PHP code execution via `_self.(\u003cstring\u003e)` macro-reference compilation"
}

CVE-2026-46640 (GCVE-0-2026-46640)

Vulnerability from cvelistv5 – Published: 2026-07-14 21:22 – Updated: 2026-07-16 03:55

Title

Twig: Arbitrary PHP code execution via `_self.(<string>)` macro-reference compilation

Summary

Twig is a template language for PHP. From 3.15.0 until 3.26.0, _self.(<string>) and import-alias dynamic attribute syntax can concatenate an attacker-controlled string into a MacroReferenceExpression name without identifier validation, causing raw PHP to be emitted into the generated template source and executed at template-load time. This issue is fixed in version 3.26.0.

Severity

8.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-15 00:00 UTC

CWE

CWE-94 - Improper Control of Generation of Code ('Code Injection')

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/twigphp/Twig/security/advisori…	x_refsource_CONFIRM
https://github.com/twigphp/Twig/commit/324fa60545…	x_refsource_MISC
https://github.com/twigphp/Twig/releases/tag/v3.26.0	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
twigphp	Twig	Affected: >= 3.15.0, < 3.26.0

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JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-46640",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-15T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-16T03:55:34.985Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Twig",
          "vendor": "twigphp",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 3.15.0, \u003c 3.26.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Twig is a template language for PHP. From 3.15.0 until 3.26.0, _self.(\u003cstring\u003e) and import-alias dynamic attribute syntax can concatenate an attacker-controlled string into a MacroReferenceExpression name without identifier validation, causing raw PHP to be emitted into the generated template source and executed at template-load time. This issue is fixed in version 3.26.0."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-94",
              "description": "CWE-94: Improper Control of Generation of Code (\u0027Code Injection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-14T21:22:57.332Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/twigphp/Twig/security/advisories/GHSA-45vw-wh46-2vx8",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/twigphp/Twig/security/advisories/GHSA-45vw-wh46-2vx8"
        },
        {
          "name": "https://github.com/twigphp/Twig/commit/324fa60545694fa6abe85ded9befcb82e1066bc2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/twigphp/Twig/commit/324fa60545694fa6abe85ded9befcb82e1066bc2"
        },
        {
          "name": "https://github.com/twigphp/Twig/releases/tag/v3.26.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/twigphp/Twig/releases/tag/v3.26.0"
        }
      ],
      "source": {
        "advisory": "GHSA-45vw-wh46-2vx8",
        "discovery": "UNKNOWN"
      },
      "title": "Twig: Arbitrary PHP code execution via `_self.(\u003cstring\u003e)` macro-reference compilation"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-46640",
    "datePublished": "2026-07-14T21:22:57.332Z",
    "dateReserved": "2026-05-15T20:11:54.584Z",
    "dateUpdated": "2026-07-16T03:55:34.985Z",
    "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.

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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