Vulnerability-Lookup

CVE-2026-49452 (GCVE-0-2026-49452)

Vulnerability from cvelistv5 – Published: 2026-08-18 17:59 – Updated: 2026-08-19 15:12

Title

WeasyPrint: CSS Injection via Presentational Hints

Summary

WeasyPrint helps web developers to create PDF documents. Prior to 69.0, WeasyPrint embeds unescaped HTML presentational-hint attribute values into CSS in weasyprint/css/__init__.py when presentational_hints=True. The background attribute is inserted into a background-image:url() declaration and parsed by tinycss2.parse_blocks_contents(), allowing untrusted HTML to inject additional CSS declarations. Applications that render untrusted HTML with presentational hints enabled can be affected by CSS injection and server-side requests through injected url() values. This issue is fixed in version 69.0.

Severity

6.5 (Medium)


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

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-19 15:12 UTC

CWE

CWE-74 - Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Assigner

GitHub_M mitre root

References

4 references

URL	Tags
https://github.com/Kozea/WeasyPrint/security/advi…	x_refsource_CONFIRM
https://github.com/Kozea/WeasyPrint/pull/2773	x_refsource_MISC
https://github.com/Kozea/WeasyPrint/commit/e15826…	x_refsource_MISC
https://github.com/Kozea/WeasyPrint/releases/tag/v69.0	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
Kozea	WeasyPrint	Affected: < 69.0	guessed

Show details on NVD website

JSON

To clipboard

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BREW-WEASYPRINT-CVE-2026-49452 (GHSA-JHHC-3HCP-QHM5)

Vulnerability from osv_homebrew – Published: 2026-08-13 17:49 – Updated: 2026-09-10 01:36 – Source website

Summary

WeasyPrint has CSS Injection via Presentational Hints

Details

Summary

A CSS injection issue exists in WeasyPrint when HTML presentational hints are enabled. Unescaped attribute values are embedded into CSS, allowing injection of arbitrary CSS declarations. This affects applications processing untrusted HTML input.

Details

File: weasyprint/css/init.py

The background attribute is used to construct CSS:

background-image:url({element.get("background")})

This string is parsed by tinycss2.parse_blocks_contents().

Because the value is not escaped, additional CSS declarations can be injected.

PoC

### Impact - CSS injection - Server-side requests via injected `url()` - Limited to cases where `presentational_hints=True` ### Suggested Fix - Escape attribute values before embedding into CSS - Restrict allowed values for presentational hints [VULN-05_css_injection_presentational_hints.md](https://github.com/user-attachments/files/26370718/VULN-05_css_injection_presentational_hints.md)

Severity

6.5 (Medium)


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

References

URL

Type

	https://github.com/Kozea/WeasyPrint/security/advi…	WEB
	https://github.com/Kozea/WeasyPrint	PACKAGE

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "weasyprint",
        "purl": "pkg:brew/weasyprint"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "69.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/weasyprint@70.0",
        "name": "weasyprint",
        "strategy": "registry",
        "subject_version": "70.0"
      },
      {
        "ecosystem": "Debian",
        "key": "Debian/weasyprint",
        "name": "weasyprint",
        "strategy": "distro"
      },
      {
        "ecosystem": "PyPI",
        "key": "upstream:pkg:pypi/weasyprint@70.0",
        "name": "weasyprint",
        "strategy": "distro",
        "subject_version": "70.0"
      },
      {
        "ecosystem": "Ubuntu",
        "key": "Ubuntu/weasyprint",
        "name": "weasyprint",
        "strategy": "distro"
      }
    ]
  },
  "details": "### Summary\nA CSS injection issue exists in WeasyPrint when HTML presentational hints are enabled. Unescaped attribute values are embedded into CSS, allowing injection of arbitrary CSS declarations. This affects applications processing untrusted HTML input.\n\n### Details\nFile: weasyprint/css/__init__.py\n\nThe `background` attribute is used to construct CSS:\n\nbackground-image:url({element.get(\"background\")})\n\nThis string is parsed by `tinycss2.parse_blocks_contents()`.\n\nBecause the value is not escaped, additional CSS declarations can be injected.\n\n### PoC\n\u003cbody background=\"x);background-image:url(http://169.254.169.254/latest/meta-data/)\"\u003e\n\n### Impact\n- CSS injection\n- Server-side requests via injected `url()`\n- Limited to cases where `presentational_hints=True`\n\n### Suggested Fix\n- Escape attribute values before embedding into CSS\n- Restrict allowed values for presentational hints\n[VULN-05_css_injection_presentational_hints.md](https://github.com/user-attachments/files/26370718/VULN-05_css_injection_presentational_hints.md)",
  "id": "BREW-weasyprint-CVE-2026-49452",
  "modified": "2026-09-10T01:36:07Z",
  "published": "2026-08-13T17:49:06Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Kozea/WeasyPrint"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "WeasyPrint has CSS Injection via Presentational Hints",
  "upstream": [
    "GHSA-jhhc-3hcp-qhm5",
    "CVE-2026-49452",
    "PYSEC-2026-3412"
  ]
}

FKIE_CVE-2026-49452

Vulnerability from fkie_nvd - Published: 2026-08-18 18:17 - Updated: 2026-09-18 20:09

Severity

6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/Kozea/WeasyPrint/commit/e158264e33fa399b29f415d30719c1d85a55df1d
	security-advisories@github.com	https://github.com/Kozea/WeasyPrint/pull/2773
	security-advisories@github.com	https://github.com/Kozea/WeasyPrint/releases/tag/v69.0
	security-advisories@github.com	https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
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          "product": "WeasyPrint",
          "vendor": "Kozea",
          "versions": [
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              "status": "affected",
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    {
      "lang": "en",
      "value": "WeasyPrint helps web developers to create PDF documents. Prior to 69.0, WeasyPrint embeds unescaped HTML presentational-hint attribute values into CSS in weasyprint/css/__init__.py when presentational_hints=True. The background attribute is inserted into a background-image:url() declaration and parsed by tinycss2.parse_blocks_contents(), allowing untrusted HTML to inject additional CSS declarations. Applications that render untrusted HTML with presentational hints enabled can be affected by CSS injection and server-side requests through injected url() values. This issue is fixed in version 69.0."
    }
  ],
  "id": "CVE-2026-49452",
  "lastModified": "2026-09-18T20:09:01.757",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-49452",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-19T15:12:11.871495Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-18T18:17:49.147",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/Kozea/WeasyPrint/commit/e158264e33fa399b29f415d30719c1d85a55df1d"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/Kozea/WeasyPrint/pull/2773"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/Kozea/WeasyPrint/releases/tag/v69.0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-74"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

GHSA-JHHC-3HCP-QHM5

Vulnerability from github – Published: 2026-07-06 17:29 – Updated: 2026-07-06 17:29

Summary

WeasyPrint has CSS Injection via Presentational Hints

Details

Summary

Details

File: weasyprint/css/init.py

The background attribute is used to construct CSS:

background-image:url({element.get("background")})

This string is parsed by tinycss2.parse_blocks_contents().

Because the value is not escaped, additional CSS declarations can be injected.

PoC

Severity

6.5 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "weasyprint"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "68.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-49452"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-74"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-06T17:29:53Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Summary\nA CSS injection issue exists in WeasyPrint when HTML presentational hints are enabled. Unescaped attribute values are embedded into CSS, allowing injection of arbitrary CSS declarations. This affects applications processing untrusted HTML input.\n\n### Details\nFile: weasyprint/css/__init__.py\n\nThe `background` attribute is used to construct CSS:\n\nbackground-image:url({element.get(\"background\")})\n\nThis string is parsed by `tinycss2.parse_blocks_contents()`.\n\nBecause the value is not escaped, additional CSS declarations can be injected.\n\n### PoC\n\u003cbody background=\"x);background-image:url(http://169.254.169.254/latest/meta-data/)\"\u003e\n\n### Impact\n- CSS injection\n- Server-side requests via injected `url()`\n- Limited to cases where `presentational_hints=True`\n\n### Suggested Fix\n- Escape attribute values before embedding into CSS\n- Restrict allowed values for presentational hints\n[VULN-05_css_injection_presentational_hints.md](https://github.com/user-attachments/files/26370718/VULN-05_css_injection_presentational_hints.md)",
  "id": "GHSA-jhhc-3hcp-qhm5",
  "modified": "2026-07-06T17:29:53Z",
  "published": "2026-07-06T17:29:53Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Kozea/WeasyPrint"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "WeasyPrint has CSS Injection via Presentational Hints"
}

OPENSUSE-SU-2026:11249-1

Vulnerability from csaf_opensuse - Published: 2026-07-10 00:00 - Updated: 2026-09-17 17:14

Summary

python313-weasyprint-69.0-1.1 on GA media

Severity

Moderate

Scope

1 vulnerability in this advisory, including CVE-2026-49452.

CVE-2026-49452

6.5 (Medium)


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

Recommended: 8 products

Open the full advisory

OPENSUSE-SU-2026:21364-1

Vulnerability from csaf_opensuse - Published: 2026-07-16 07:28 - Updated: 2026-09-17 17:39

Summary

Security update for python-weasyprint

Severity

Moderate

Scope

1 vulnerability in this advisory, including CVE-2026-49452.

CVE-2026-49452

6.5 (Medium)


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

Recommended: 1 product

Open the full advisory

PYSEC-2026-3412

Vulnerability from pysec - Published: 2026-07-13 15:46 - Updated: 2026-07-13 16:07

Details

Summary

Details

File: weasyprint/css/init.py

The background attribute is used to construct CSS:

background-image:url({element.get("background")})

This string is parsed by tinycss2.parse_blocks_contents().

Because the value is not escaped, additional CSS declarations can be injected.

PoC

Severity

6.5 (Medium)


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

Impacted products

Name	purl
weasyprint	pkg:pypi/weasyprint

Aliases

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "weasyprint",
        "purl": "pkg:pypi/weasyprint"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "68.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.1",
        "0.10",
        "0.11",
        "0.12",
        "0.13",
        "0.14",
        "0.15",
        "0.16",
        "0.17",
        "0.17.1",
        "0.18",
        "0.19",
        "0.19.1",
        "0.19.2",
        "0.2",
        "0.2.1",
        "0.2.2",
        "0.20",
        "0.20.1",
        "0.20.2",
        "0.21",
        "0.22",
        "0.23",
        "0.24",
        "0.25",
        "0.26",
        "0.27",
        "0.28",
        "0.29",
        "0.3",
        "0.3.1",
        "0.30",
        "0.31",
        "0.32",
        "0.33",
        "0.34",
        "0.35",
        "0.36",
        "0.37",
        "0.38",
        "0.39",
        "0.4",
        "0.40",
        "0.41",
        "0.42",
        "0.42.1",
        "0.42.2",
        "0.42.3",
        "0.5",
        "0.6",
        "0.6.1",
        "0.7",
        "0.7.1",
        "0.8",
        "0.9",
        "43",
        "43rc1",
        "43rc2",
        "44",
        "45",
        "46",
        "47",
        "48",
        "49",
        "50",
        "51",
        "52",
        "52.1",
        "52.2",
        "52.3",
        "52.4",
        "52.5",
        "53.0",
        "53.0b1",
        "53.0b2",
        "53.1",
        "53.2",
        "53.3",
        "53.4",
        "54.0",
        "54.0b1",
        "54.1",
        "54.2",
        "54.3",
        "55.0",
        "55.0b1",
        "56.0",
        "56.0b1",
        "56.1",
        "57.0",
        "57.0b1",
        "57.1",
        "57.2",
        "58.0",
        "58.0b1",
        "58.1",
        "59.0",
        "59.0b1",
        "60.0",
        "60.1",
        "60.2",
        "61.0",
        "61.1",
        "61.2",
        "62.0",
        "62.1",
        "62.2",
        "62.3",
        "63.0",
        "63.1",
        "64.0",
        "64.1",
        "65.0",
        "65.1",
        "66.0",
        "67.0",
        "68.0",
        "68.1"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-49452",
    "GHSA-jhhc-3hcp-qhm5"
  ],
  "details": "### Summary\nA CSS injection issue exists in WeasyPrint when HTML presentational hints are enabled. Unescaped attribute values are embedded into CSS, allowing injection of arbitrary CSS declarations. This affects applications processing untrusted HTML input.\n\n### Details\nFile: weasyprint/css/__init__.py\n\nThe `background` attribute is used to construct CSS:\n\nbackground-image:url({element.get(\"background\")})\n\nThis string is parsed by `tinycss2.parse_blocks_contents()`.\n\nBecause the value is not escaped, additional CSS declarations can be injected.\n\n### PoC\n\u003cbody background=\"x);background-image:url(http://169.254.169.254/latest/meta-data/)\"\u003e\n\n### Impact\n- CSS injection\n- Server-side requests via injected `url()`\n- Limited to cases where `presentational_hints=True`\n\n### Suggested Fix\n- Escape attribute values before embedding into CSS\n- Restrict allowed values for presentational hints\n[VULN-05_css_injection_presentational_hints.md](https://github.com/user-attachments/files/26370718/VULN-05_css_injection_presentational_hints.md)",
  "id": "PYSEC-2026-3412",
  "modified": "2026-07-13T16:07:30.045914Z",
  "published": "2026-07-13T15:46:28.116294Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Kozea/WeasyPrint"
    },
    {
      "type": "PACKAGE",
      "url": "https://pypi.org/project/weasyprint"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-jhhc-3hcp-qhm5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-49452"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "WeasyPrint has CSS Injection via Presentational Hints"
}

UBUNTU-CVE-2026-49452 (CVE-2026-49452)

Vulnerability from osv_ubuntu – Published: 2026-08-18 18:17 – Updated: 2026-09-02 16:18 – Source website

Details

WeasyPrint helps web developers to create PDF documents. Prior to 69.0, WeasyPrint embeds unescaped HTML presentational-hint attribute values into CSS in weasyprint/css/init.py when presentational_hints=True. The background attribute is inserted into a background-image:url() declaration and parsed by tinycss2.parse_blocks_contents(), allowing untrusted HTML to inject additional CSS declarations. Applications that render untrusted HTML with presentational hints enabled can be affected by CSS injection and server-side requests through injected url() values. This issue is fixed in version 69.0.

Severity

6.5 (Medium)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-49452	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-49452	REPORT
	https://www.courtbouillon.org/blog/00067-weasyprint-69/	REPORT
	https://github.com/Kozea/WeasyPrint/security/advi…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "weasyprint",
            "binary_version": "51-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "weasyprint",
        "purl": "pkg:deb/ubuntu/weasyprint@51-2?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "50-2",
        "51-1",
        "51-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "weasyprint",
            "binary_version": "54.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "weasyprint",
        "purl": "pkg:deb/ubuntu/weasyprint@54.1-1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "51-2",
        "51-3",
        "53.4-1",
        "54.0-1",
        "54.1-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "weasyprint",
            "binary_version": "61.1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "weasyprint",
        "purl": "pkg:deb/ubuntu/weasyprint@61.1-1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "59.0-1",
        "60.2-1",
        "61.0-1",
        "61.1-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "weasyprint",
            "binary_version": "62.3-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "weasyprint",
        "purl": "pkg:deb/ubuntu/weasyprint@62.3-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "62.3-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "weasyprint",
            "binary_version": "67.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "weasyprint",
        "purl": "pkg:deb/ubuntu/weasyprint@67.0-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "62.3-1",
        "62.3-1build1",
        "67.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "WeasyPrint helps web developers to create PDF documents. Prior to 69.0, WeasyPrint embeds unescaped HTML presentational-hint attribute values into CSS in weasyprint/css/__init__.py when presentational_hints=True. The background attribute is inserted into a background-image:url() declaration and parsed by tinycss2.parse_blocks_contents(), allowing untrusted HTML to inject additional CSS declarations. Applications that render untrusted HTML with presentational hints enabled can be affected by CSS injection and server-side requests through injected url() values. This issue is fixed in version 69.0.",
  "id": "UBUNTU-CVE-2026-49452",
  "modified": "2026-09-02T16:18:22Z",
  "published": "2026-08-18T18:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-49452"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-49452"
    },
    {
      "type": "REPORT",
      "url": "https://www.courtbouillon.org/blog/00067-weasyprint-69/"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-49452"
  ]
}

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.

Action not permitted

CVE-2026-49452 (GCVE-0-2026-49452)

BREW-WEASYPRINT-CVE-2026-49452 (GHSA-JHHC-3HCP-QHM5)

Summary

Details

PoC

FKIE_CVE-2026-49452

GHSA-JHHC-3HCP-QHM5

Summary

Details

PoC

OPENSUSE-SU-2026:11249-1

OPENSUSE-SU-2026:21364-1

PYSEC-2026-3412

Summary

Details

PoC

UBUNTU-CVE-2026-49452 (CVE-2026-49452)

Tags

Sightings

Nomenclature

Related by attack behaviour