JupyterLab Git: Stored XSS leading to RCE

{
  "id": "ab6db8d82ce39ca07fb60bb10a28e6d0e23f148d6f5c1cd51bec20999954754d",
  "url": "https://osv.dev/vulnerability/CVE-2026-54527",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "JupyterLab Git: Stored XSS leading to RCE",
    "summary": "JupyterLab Git is a Git extension for JupyterLab. From 0.30.0b3 before 0.54.0, the PlainTextDiff.ts createHeader() method passes Git filenames directly to innerHTML when rendering renamed files in commit history, allowing a crafted filename to execute JavaScript when a victim views the rename diff in the Git History tab. This issue is fixed in version 0.54.0.",
    "evidence": "osv:CVE-2026-54527",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2026-54527",
      "aliases": [
        "CVE-2026-54527",
        "GHSA-f962-v9hr-pfg5",
        "PYSEC-2026-2540",
        "PYSEC-2026-2541"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/jupyterlab/jupyterlab-git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "ef622d2ce8d9b5cfb866d1712f6c5dc3f251f8b4"
                },
                {
                  "fixed": "ccbf077d2149c6b2ed35eae8a7123ae129c022aa"
                },
                {
                  "introduced": "b582faf9a46b5e1f20ad1645f83fb5ba09e0ec91"
                },
                {
                  "fixed": "c6d37b88f36aa59aee317930b95e427fb9d6b09b"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:jupyter:jupyterlab-git:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0.30.1"
                      },
                      {
                        "fixed": "0.54.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:jupyter:jupyterlab-git:0.30.0:-:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0.30.0-NA"
                      },
                      {
                        "last_affected": "0.30.0-NA"
                      }
                    ],
                    "source": "CPE_STRING"
                  },
                  {
                    "range": [
                      {
                        "fixed": "c6d37b88f36aa59aee317930b95e427fb9d6b09b"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ccbf077d2149c6b2ed35eae8a7123ae129c022aa"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v0.54.0"
                  }
                ]
              }
            }
          ],
          "versions": [
            "0.30.0-NA",
            "v0.54.0a1",
            "v0.54.0a0",
            "v0.53.0",
            "v0.53.0a1",
            "v0.53.0a0",
            "v0.52.0",
            "v0.51.4",
            "v0.51.3",
            "v0.51.2",
            "v0.51.1",
            "v0.51.0",
            "v0.50.2",
            "v0.50.1",
            "v0.50.0",
            "v0.50.0rc0",
            "v0.44.0",
            "v0.50.0a2",
            "v0.50.0a1",
            "v0.50.0a0",
            "v0.43.0",
            "v0.42.0",
            "v0.42.0rc0",
            "v0.41.0",
            "v0.40.1",
            "v0.40.0",
            "v0.39.3.post1",
            "v0.39.3",
            "v0.39.2",
            "v0.39.1",
            "v0.39.0",
            "v0.38.0",
            "v0.37.1",
            "v0.37.0",
            "v0.36.0",
            "v0.35.0",
            "v0.34.2",
            "v0.34.1",
            "v0.34.0",
            "v0.33.0",
            "v0.32.2",
            "v0.32.1",
            "v0.32.0",
            "v0.31.0",
            "v0.31.0a0",
            "v0.30.1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54527.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:52.120265286Z",
      "provider": "osv",
      "references": [
        "https://github.com/jupyterlab/jupyterlab-git/releases/tag/v0.54.0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54527.json",
        "https://github.com/jupyterlab/jupyterlab-git/security/advisories/GHSA-f962-v9hr-pfg5",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-54527",
        "https://github.com/jupyterlab/jupyterlab-git/commit/c6d37b88f36aa59aee317930b95e427fb9d6b09b"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54527.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-54527",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 520942,
  "published_at": "2026-07-08T21:03:01.698+00:00"
}