Skip to content
Heist/ feed
Back to feed
Medium

sigstore legacy TUF client allows for arbitrary file writes with target cache path traversal

Type: advisorySources: OSV

sigstore framework is a common go library shared across sigstore services and clients. In versions 1.10.3 and below, the legacy TUF client (pkg/tuf/client.go) supports caching target files to disk. It constructs a filesystem path by joining a cache base directory with a target name sourced from signed target metadata; however, it does not validate that the resulting path stays within the cache base directory. A malicious TUF repository can trigger arbitrary file overwriting, limited to the permissions that the calling process has. Note that this should only affect clients that are directly using the TUF client in sigstore/sigstore or are using an older version of Cosign. Public Sigstore deployment users are unaffected, as TUF metadata is validated by a quorum of trusted collaborators. This issue has been fixed in version 1.10.4. As a workaround, users can disable disk caching for the legacy client by setting SIGSTORE_NO_CACHE=true in the environment, migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf, or upgrade to the latest sigstore/sigstore release.

Products
Not specified
Affected versions
Not specified
Fixed versions
Not specified
CVEs
CVE-2026-24137
Confirmed fixed CVEs
Not specified
Updated in this feed
5 Nov 2026, 01:19 UTC · Revision 1

Source evidence

sigstore legacy TUF client allows for arbitrary file writes with target cache path traversal

core-osv · Original source

Published 23 Jan 2026, 00:04 UTC

sigstore framework is a common go library shared across sigstore services and clients. In versions 1.10.3 and below, the legacy TUF client (pkg/tuf/client.go) supports caching target files to disk. It constructs a filesystem path by joining a cache base directory with a target name sourced from signed target metadata; however, it does not validate that the resulting path stays within the cache base directory. A malicious TUF repository can trigger arbitrary file overwriting, limited to the permissions that the calling process has. Note that this should only affect clients that are directly using the TUF client in sigstore/sigstore or are using an older version of Cosign. Public Sigstore deployment users are unaffected, as TUF metadata is validated by a quorum of trusted collaborators. This issue has been fixed in version 1.10.4. As a workaround, users can disable disk caching for the legacy client by setting SIGSTORE_NO_CACHE=true in the environment, migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf, or upgrade to the latest sigstore/sigstore release.

osv:CVE-2026-24137
Complete source record
{
  "id": "b80993fa2160600233b8e7e34e5e6ea63de2f039b1fa4d3ed847a1c5424c40a6",
  "url": "https://osv.dev/vulnerability/CVE-2026-24137",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "sigstore legacy TUF client allows for arbitrary file writes with target cache path traversal",
    "summary": "sigstore framework is a common go library shared across sigstore services and clients. In versions 1.10.3 and below, the legacy TUF client (pkg/tuf/client.go) supports caching target files to disk. It constructs a filesystem path by joining a cache base directory with a target name sourced from signed target metadata; however, it does not validate that the resulting path stays within the cache base directory. A malicious TUF repository can trigger arbitrary file overwriting, limited to the permissions that the calling process has. Note that this should only affect clients that are directly using the TUF client in sigstore/sigstore or are using an older version of Cosign. Public Sigstore deployment users are unaffected, as TUF metadata is validated by a quorum of trusted collaborators. This issue has been fixed in version 1.10.4. As a workaround, users can disable disk caching for the legacy client by setting SIGSTORE_NO_CACHE=true in the environment, migrate to https://github.com/sigstore/sigstore-go/tree/main/pkg/tuf, or upgrade to the latest sigstore/sigstore release.",
    "evidence": "osv:CVE-2026-24137",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-24137",
      "aliases": [
        "CVE-2026-24137",
        "GHSA-fcv2-xgw5-pqxf",
        "GO-2026-4358"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/sigstore/sigstore",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "8ec410a2993ea78083aecf0e473a85453039496e"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.10.4"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "8ec410a2993ea78083aecf0e473a85453039496e"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "8ec410a2993ea78083aecf0e473a85453039496e"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v1.10.4"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v1.10.3",
            "pkg/signature/kms/hashivault/v1.10.3",
            "pkg/signature/kms/gcp/v1.10.3",
            "pkg/signature/kms/azure/v1.10.3",
            "pkg/signature/kms/aws/v1.10.3",
            "v1.10.2",
            "pkg/signature/kms/hashivault/v1.10.2",
            "pkg/signature/kms/gcp/v1.10.2",
            "pkg/signature/kms/azure/v1.10.2",
            "pkg/signature/kms/aws/v1.10.2",
            "v1.10.0",
            "pkg/signature/kms/hashivault/v1.10.0",
            "pkg/signature/kms/gcp/v1.10.0",
            "pkg/signature/kms/azure/v1.10.0",
            "pkg/signature/kms/aws/v1.10.0",
            "v1.9.5",
            "pkg/signature/kms/hashivault/v1.9.5",
            "pkg/signature/kms/gcp/v1.9.5",
            "pkg/signature/kms/azure/v1.9.5",
            "pkg/signature/kms/aws/v1.9.5",
            "v1.9.4",
            "pkg/signature/kms/hashivault/v1.9.4",
            "pkg/signature/kms/gcp/v1.9.4",
            "pkg/signature/kms/azure/v1.9.4",
            "pkg/signature/kms/aws/v1.9.4",
            "v1.9.3",
            "pkg/signature/kms/hashivault/v1.9.3",
            "pkg/signature/kms/gcp/v1.9.3",
            "pkg/signature/kms/azure/v1.9.3",
            "pkg/signature/kms/aws/v1.9.3",
            "v1.9.2",
            "pkg/signature/kms/hashivault/v1.9.2",
            "pkg/signature/kms/gcp/v1.9.2",
            "pkg/signature/kms/azure/v1.9.2",
            "pkg/signature/kms/aws/v1.9.2",
            "v1.9.1",
            "pkg/signature/kms/hashivault/v1.9.1",
            "pkg/signature/kms/gcp/v1.9.1",
            "pkg/signature/kms/azure/v1.9.1",
            "pkg/signature/kms/aws/v1.9.1",
            "v1.9.0",
            "pkg/signature/kms/hashivault/v1.9.0",
            "pkg/signature/kms/gcp/v1.9.0",
            "pkg/signature/kms/azure/v1.9.0",
            "pkg/signature/kms/aws/v1.9.0",
            "v1.8.15",
            "pkg/signature/kms/hashivault/v1.8.15",
            "pkg/signature/kms/gcp/v1.8.15",
            "pkg/signature/kms/azure/v1.8.15",
            "pkg/signature/kms/aws/v1.8.15",
            "v1.8.14",
            "pkg/signature/kms/hashivault/v1.8.14",
            "pkg/signature/kms/gcp/v1.8.14",
            "pkg/signature/kms/azure/v1.8.14",
            "pkg/signature/kms/aws/v1.8.14",
            "v1.8.13",
            "v1.8.12",
            "pkg/signature/kms/hashivault/v1.8.12",
            "pkg/signature/kms/gcp/v1.8.12",
            "pkg/signature/kms/azure/v1.8.12",
            "pkg/signature/kms/aws/v1.8.12",
            "v1.8.11",
            "pkg/signature/kms/hashivault/v1.8.11",
            "pkg/signature/kms/gcp/v1.8.11",
            "pkg/signature/kms/azure/v1.8.11",
            "pkg/signature/kms/aws/v1.8.11",
            "v1.8.10",
            "pkg/signature/kms/hashivault/v1.8.10",
            "pkg/signature/kms/gcp/v1.8.10",
            "pkg/signature/kms/azure/v1.8.10",
            "pkg/signature/kms/aws/v1.8.10",
            "v1.8.9",
            "pkg/signature/kms/hashivault/v1.8.9",
            "pkg/signature/kms/gcp/v1.8.9",
            "pkg/signature/kms/azure/v1.8.9",
            "pkg/signature/kms/aws/v1.8.9",
            "v1.8.8",
            "pkg/signature/kms/hashivault/v1.8.8",
            "pkg/signature/kms/gcp/v1.8.8",
            "pkg/signature/kms/azure/v1.8.8",
            "pkg/signature/kms/aws/v1.8.8",
            "v1.8.7",
            "pkg/signature/kms/hashivault/v1.8.7",
            "pkg/signature/kms/gcp/v1.8.7",
            "pkg/signature/kms/azure/v1.8.7",
            "pkg/signature/kms/aws/v1.8.7",
            "v1.8.6",
            "pkg/signature/kms/hashivault/v1.8.6",
            "pkg/signature/kms/gcp/v1.8.6",
            "pkg/signature/kms/azure/v1.8.6",
            "pkg/signature/kms/aws/v1.8.6",
            "v1.8.5",
            "pkg/signature/kms/hashivault/v1.8.5",
            "pkg/signature/kms/gcp/v1.8.5",
            "pkg/signature/kms/azure/v1.8.5",
            "pkg/signature/kms/aws/v1.8.5",
            "v1.8.4",
            "pkg/signature/kms/hashivault/v1.8.4",
            "pkg/signature/kms/gcp/v1.8.4",
            "pkg/signature/kms/azure/v1.8.4",
            "pkg/signature/kms/aws/v1.8.4",
            "v1.8.3",
            "pkg/signature/kms/hashivault/v1.8.3",
            "pkg/signature/kms/gcp/v1.8.3",
            "pkg/signature/kms/azure/v1.8.3",
            "pkg/signature/kms/aws/v1.8.3",
            "v1.8.2",
            "pkg/signature/kms/hashivault/v1.8.2",
            "pkg/signature/kms/gcp/v1.8.2",
            "pkg/signature/kms/azure/v1.8.2",
            "pkg/signature/kms/aws/v1.8.2",
            "v1.8.1",
            "pkg/signature/kms/hashivault/v1.8.1",
            "pkg/signature/kms/gcp/v1.8.1",
            "pkg/signature/kms/azure/v1.8.1",
            "pkg/signature/kms/aws/v1.8.1",
            "v1.8.0",
            "pkg/signature/kms/hashivault/v1.8.0",
            "pkg/signature/kms/gcp/v1.8.0",
            "pkg/signature/kms/azure/v1.8.0",
            "pkg/signature/kms/aws/v1.8.0",
            "v1.7.6",
            "pkg/signature/kms/hashivault/v1.7.6",
            "pkg/signature/kms/gcp/v1.7.6",
            "pkg/signature/kms/azure/v1.7.6",
            "pkg/signature/kms/aws/v1.7.6",
            "v1.7.5",
            "pkg/signature/kms/hashivault/v1.7.5",
            "pkg/signature/kms/gcp/v1.7.5",
            "pkg/signature/kms/azure/v1.7.5",
            "pkg/signature/kms/aws/v1.7.5",
            "v1.7.4",
            "pkg/signature/kms/hashivault/v1.7.4",
            "pkg/signature/kms/gcp/v1.7.4",
            "pkg/signature/kms/azure/v1.7.4",
            "pkg/signature/kms/aws/v1.7.4",
            "v1.7.3",
            "pkg/signature/kms/hashivault/v1.7.3",
            "pkg/signature/kms/gcp/v1.7.3",
            "pkg/signature/kms/azure/v1.7.3",
            "pkg/signature/kms/aws/v1.7.3",
            "v1.7.2",
            "pkg/signature/kms/hashivault/v1.7.2",
            "pkg/signature/kms/gcp/v1.7.2",
            "pkg/signature/kms/azure/v1.7.2",
            "pkg/signature/kms/aws/v1.7.2",
            "v1.7.1",
            "pkg/signature/kms/hashivault/v1.7.1",
            "pkg/signature/kms/gcp/v1.7.1",
            "pkg/signature/kms/azure/v1.7.1",
            "pkg/signature/kms/aws/v1.7.1",
            "v1.7.0",
            "pkg/signature/kms/hashivault/v1.7.0",
            "pkg/signature/kms/gcp/v1.7.0",
            "pkg/signature/kms/azure/v1.7.0",
            "pkg/signature/kms/aws/v1.7.0",
            "v1.6.5",
            "pkg/signature/kms/hashivault/v1.6.5",
            "pkg/signature/kms/gcp/v1.6.5",
            "pkg/signature/kms/azure/v1.6.5",
            "pkg/signature/kms/aws/v1.6.5",
            "v1.6.4",
            "v1.6.3",
            "v1.6.2",
            "v1.6.1",
            "v1.6.0",
            "v1.5.2",
            "v1.5.1",
            "v1.5.0",
            "v1.4.6",
            "v1.4.5",
            "v1.4.4",
            "v1.4.3",
            "v1.4.2",
            "v1.4.1",
            "v1.4.0",
            "v1.3.1",
            "v1.3.0",
            "v1.2.0",
            "v1.1.0",
            "v1.0.1",
            "v1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-24137.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:41.545767164Z",
      "provider": "osv",
      "references": [
        "https://github.com/sigstore/sigstore/releases/tag/v1.10.4",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/24xxx/CVE-2026-24137.json",
        "https://github.com/sigstore/sigstore/security/advisories/GHSA-fcv2-xgw5-pqxf",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-24137",
        "https://github.com/sigstore/sigstore/commit/8ec410a2993ea78083aecf0e473a85453039496e"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-22"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/24xxx/CVE-2026-24137.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-24137",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 509010,
  "published_at": "2026-01-23T00:04:19.046+00:00"
}