Vulnerability Instance
Lookup for vulnerabilities affecting packages.
GET /api/vulnerabilities/20789?format=api
{ "url": "http://public2.vulnerablecode.io/api/vulnerabilities/20789?format=api", "vulnerability_id": "VCID-93qu-3cgz-j7a2", "summary": "Cosign verification accepts any valid Rekor entry under certain conditions\n### Impact\n\nA Cosign bundle can be crafted to successfully verify an artifact even if the embedded Rekor entry does not reference the artifact's digest, signature or public key. When verifying a Rekor entry, Cosign verifies the Rekor entry signature, and also compares the artifact's digest, the user's public key from either a Fulcio certificate or provided by the user, and the artifact signature to the Rekor entry contents. Without these comparisons, Cosign would accept any response from Rekor as valid. A malicious actor that has compromised a user's identity or signing key could construct a valid Cosign bundle by including any arbitrary Rekor entry, thus preventing the user from being able to audit the signing event.\n\nThis vulnerability only affects users that provide a trusted root via `--trusted-root` or when fetched automatically from a TUF repository, when no trusted key material is provided via `SIGSTORE_REKOR_PUBLIC_KEY`. When using the default flag values in Cosign v3 to sign and verify (`--use-signing-config=true` and `--new-bundle-format=true` for signing, `--new-bundle-format=true` for verification), users are unaffected. Cosign v2 users are affected using the default flag values.\n\nThis issue had previously been fixed in https://github.com/sigstore/cosign/security/advisories/GHSA-8gw7-4j42-w388 but recent refactoring caused a regression. We have added testing to prevent a future regression.\n\n#### Steps to Reproduce\n\n```\necho blob > /tmp/blob\ncosign sign-blob -y --new-bundle-format=false --bundle /tmp/bundle.1 --use-signing-config=false /tmp/blob\ncosign sign-blob -y --new-bundle-format=false --bundle /tmp/bundle.2 --use-signing-config=false /tmp/blob\njq \".rekorBundle |= $(jq .rekorBundle /tmp/bundle.2)\" /tmp/bundle.1 > /tmp/bundle.3\ncosign verify-blob --bundle /tmp/bundle.3 --certificate-identity-regexp='.*' --certificate-oidc-issuer-regexp='.*' /tmp/blob\n```\n\n### Patches\n\nUpgrade to Cosign v2.6.2 or Cosign v3.0.4. This does not affect Cosign v1.\n\n### Workarounds\n\nYou can provide trusted key material via a set of flags under certain conditions. The simplest fix is to upgrade to the latest Cosign v2 or v3 release.\n\nNote that the example below works for `cosign verify`, `cosign verify-blob, `cosign verify-blob-attestation`, and `cosign verify-attestation`.\n\n```\nSIGSTORE_REKOR_PUBLIC_KEY=<path to Rekor pub key> cosign verify-blob --use-signing-config=false --new-bundle-format=false --bundle=<path to bundle> <artifact>\n```", "aliases": [ { "alias": "CVE-2026-22703" }, { "alias": "GHSA-whqx-f9j3-ch6m" } ], "fixed_packages": [ { "url": "http://public2.vulnerablecode.io/api/packages/584957?format=api", "purl": "pkg:deb/debian/cosign@2.6.2-1?distro=trixie", "is_vulnerable": true, "affected_by_vulnerabilities": [ { "vulnerability": "VCID-8k12-ju2w-cygz" } ], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/cosign@2.6.2-1%3Fdistro=trixie" }, { "url": "http://public2.vulnerablecode.io/api/packages/586244?format=api", "purl": "pkg:deb/debian/cosign@2.6.2-1", "is_vulnerable": true, "affected_by_vulnerabilities": [ { "vulnerability": "VCID-8k12-ju2w-cygz" } ], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/cosign@2.6.2-1" }, { "url": "http://public2.vulnerablecode.io/api/packages/1063043?format=api", "purl": "pkg:deb/debian/cosign@2.6.3-1?distro=trixie", "is_vulnerable": false, "affected_by_vulnerabilities": [], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/cosign@2.6.3-1%3Fdistro=trixie" }, { "url": "http://public2.vulnerablecode.io/api/packages/62592?format=api", "purl": "pkg:golang/github.com/sigstore/cosign/v2@2.6.2", "is_vulnerable": false, "affected_by_vulnerabilities": [], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:golang/github.com/sigstore/cosign/v2@2.6.2" }, { "url": "http://public2.vulnerablecode.io/api/packages/62590?format=api", "purl": "pkg:golang/github.com/sigstore/cosign/v3@3.0.4", "is_vulnerable": false, "affected_by_vulnerabilities": [], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:golang/github.com/sigstore/cosign/v3@3.0.4" } ], "affected_packages": [ { "url": "http://public2.vulnerablecode.io/api/packages/584956?format=api", "purl": "pkg:deb/debian/cosign@2.5.0-2?distro=trixie", "is_vulnerable": true, "affected_by_vulnerabilities": [ { "vulnerability": "VCID-8k12-ju2w-cygz" }, { "vulnerability": "VCID-93qu-3cgz-j7a2" } ], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/cosign@2.5.0-2%3Fdistro=trixie" }, { "url": "http://public2.vulnerablecode.io/api/packages/586243?format=api", "purl": "pkg:deb/debian/cosign@2.5.0-2", "is_vulnerable": true, "affected_by_vulnerabilities": [ { "vulnerability": "VCID-8k12-ju2w-cygz" }, { "vulnerability": "VCID-93qu-3cgz-j7a2" } ], "resource_url": "http://public2.vulnerablecode.io/packages/pkg:deb/debian/cosign@2.5.0-2" } ], "references": [ { "reference_url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-22703.json", "reference_id": "", "reference_type": "", "scores": [ { "value": "5.5", "scoring_system": "cvssv3", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N" } ], "url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-22703.json" }, { "reference_url": "https://api.first.org/data/v1/epss?cve=CVE-2026-22703", "reference_id": "", "reference_type": "", "scores": [ { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00377", "published_at": "2026-05-05T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00375", "published_at": "2026-04-29T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00378", "published_at": "2026-04-24T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00352", "published_at": "2026-04-16T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00357", "published_at": "2026-04-18T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00358", "published_at": "2026-04-12T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00363", "published_at": "2026-04-09T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00362", "published_at": "2026-04-11T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00366", "published_at": "2026-04-07T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00376", "published_at": "2026-04-02T12:55:00Z" }, { "value": "6e-05", "scoring_system": "epss", "scoring_elements": "0.00379", "published_at": "2026-04-26T12:55:00Z" } ], "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-22703" }, { "reference_url": "https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml", "reference_id": "", "reference_type": "", "scores": [ { "value": "5.5", "scoring_system": "cvssv3.1", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N" } ], "url": "https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml" }, { "reference_url": "https://github.com/sigstore/cosign", "reference_id": "", "reference_type": "", "scores": [ { "value": "5.5", "scoring_system": "cvssv3.1", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N" }, { "value": "MODERATE", "scoring_system": "generic_textual", "scoring_elements": "" } ], "url": "https://github.com/sigstore/cosign" }, { "reference_url": "https://github.com/sigstore/cosign/commit/6832fba4928c1ad69400235bbc41212de5006176", "reference_id": "", "reference_type": "", "scores": [ { "value": "5.5", "scoring_system": "cvssv3.1", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N" }, { "value": "MODERATE", "scoring_system": "generic_textual", "scoring_elements": "" }, { "value": "Track", "scoring_system": "ssvc", "scoring_elements": "SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-01-12T16:43:50Z/" } ], "url": "https://github.com/sigstore/cosign/commit/6832fba4928c1ad69400235bbc41212de5006176" }, { "reference_url": "https://github.com/sigstore/cosign/pull/4623", "reference_id": "", "reference_type": "", "scores": [ { "value": "5.5", "scoring_system": "cvssv3.1", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N" }, { "value": "MODERATE", "scoring_system": "generic_textual", "scoring_elements": "" }, { "value": "Track", "scoring_system": "ssvc", "scoring_elements": "SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-01-12T16:43:50Z/" } ], "url": "https://github.com/sigstore/cosign/pull/4623" }, { "reference_url": "https://github.com/sigstore/cosign/security/advisories/GHSA-whqx-f9j3-ch6m", "reference_id": "", "reference_type": "", "scores": [ { "value": "5.5", "scoring_system": "cvssv3.1", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N" }, { "value": "MODERATE", "scoring_system": "generic_textual", "scoring_elements": "" }, { "value": "Track", "scoring_system": "ssvc", "scoring_elements": "SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-01-12T16:43:50Z/" } ], "url": "https://github.com/sigstore/cosign/security/advisories/GHSA-whqx-f9j3-ch6m" }, { "reference_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-22703", "reference_id": "", "reference_type": "", "scores": [ { "value": "5.5", "scoring_system": "cvssv3.1", "scoring_elements": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N" }, { "value": "MODERATE", "scoring_system": "generic_textual", "scoring_elements": "" } ], "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-22703" }, { "reference_url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1126764", "reference_id": "1126764", "reference_type": "", "scores": [], "url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1126764" }, { "reference_url": "https://bugzilla.redhat.com/show_bug.cgi?id=2428445", "reference_id": "2428445", "reference_type": "", "scores": [], "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2428445" } ], "weaknesses": [ { "cwe_id": 345, "name": "Insufficient Verification of Data Authenticity", "description": "The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data." } ], "exploits": [], "severity_range_score": "4.0 - 6.9", "exploitability": "0.5", "weighted_severity": "6.2", "risk_score": 3.1, "resource_url": "http://public2.vulnerablecode.io/vulnerabilities/VCID-93qu-3cgz-j7a2" }