Vulnerability-Lookup

ubuntu-cve-2026-49452

Vulnerability from osv_ubuntu

Published

2026-08-18 18:17

Modified

2026-09-02 16:18

Summary

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"
  ]
}

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
Kozea	WeasyPrint	Affected: < 69.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-49452",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-19T15:12:11.871495Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-19T15:12:42.865Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "WeasyPrint",
          "vendor": "Kozea",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 69.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "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"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-74",
              "description": "CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component (\u0027Injection\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-18T17:59:36.144Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/Kozea/WeasyPrint/security/advisories/GHSA-jhhc-3hcp-qhm5"
        },
        {
          "name": "https://github.com/Kozea/WeasyPrint/pull/2773",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/Kozea/WeasyPrint/pull/2773"
        },
        {
          "name": "https://github.com/Kozea/WeasyPrint/commit/e158264e33fa399b29f415d30719c1d85a55df1d",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/Kozea/WeasyPrint/commit/e158264e33fa399b29f415d30719c1d85a55df1d"
        },
        {
          "name": "https://github.com/Kozea/WeasyPrint/releases/tag/v69.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/Kozea/WeasyPrint/releases/tag/v69.0"
        }
      ],
      "source": {
        "advisory": "GHSA-jhhc-3hcp-qhm5",
        "discovery": "UNKNOWN"
      },
      "title": "WeasyPrint: CSS Injection via Presentational Hints"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-49452",
    "datePublished": "2026-08-18T17:59:36.144Z",
    "dateReserved": "2026-05-30T02:43:33.106Z",
    "dateUpdated": "2026-08-19T15:12:42.865Z",
    "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.