Vulnerability-Lookup

UBUNTU-CVE-2026-24122 (CVE-2026-24122)

Vulnerability from osv_ubuntu – Published: 2026-02-19 23:16 – Updated: 2026-07-02 16:11 – Source website

Details

Cosign provides code signing and transparency for containers and binaries. In versions 3.0.4 and below, an issuing certificate with a validity that expires before the leaf certificate will be considered valid during verification even if the provided timestamp would mean the issuing certificate should be considered expired. When verifying artifact signatures using a certificate, Cosign first verifies the certificate chain using the leaf certificate's "not before" timestamp and later checks expiry of the leaf certificate using either a signed timestamp provided by the Rekor transparency log or from a timestamp authority, or using the current time. The root and all issuing certificates are assumed to be valid during the leaf certificate's validity. There is no impact to users of the public Sigstore infrastructure. This may affect private deployments with customized PKIs. This issue has been fixed in version 3.0.5.

Severity

3.7 (Low)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-24122	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-24122	REPORT
	https://github.com/sigstore/cosign/commit/3c9a736…	REPORT
	https://github.com/sigstore/cosign/releases/tag/v3.0.5	REPORT
	https://github.com/sigstore/cosign/security/advis…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "cosign",
            "binary_version": "2.5.0-2"
          },
          {
            "binary_name": "golang-github-sigstore-cosign-dev",
            "binary_version": "2.5.0-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "cosign",
        "purl": "pkg:deb/ubuntu/cosign@2.5.0-2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.4.3-1",
        "2.5.0-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "cosign",
            "binary_version": "2.6.2-1ubuntu0.26.04.1~esm1"
          },
          {
            "binary_name": "golang-github-sigstore-cosign-dev",
            "binary_version": "2.6.2-1ubuntu0.26.04.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:26.04:LTS",
        "name": "cosign",
        "purl": "pkg:deb/ubuntu/cosign@2.6.2-1ubuntu0.26.04.1~esm1?arch=source\u0026distro=esm-apps/resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.5.0-2",
        "2.5.0-2build1",
        "2.6.2-1",
        "2.6.2-1ubuntu0.26.04.1~esm1"
      ]
    }
  ],
  "aliases": [],
  "details": "Cosign provides code signing and transparency for containers and binaries. In versions 3.0.4 and below, an issuing certificate with a validity that expires before the leaf certificate will be considered valid during verification even if the provided timestamp would mean the issuing certificate should be considered expired. When verifying artifact signatures using a certificate, Cosign first verifies the certificate chain using the leaf certificate\u0027s \"not before\" timestamp and later checks expiry of the leaf certificate using either a signed timestamp provided by the Rekor transparency log or from a timestamp authority, or using the current time. The root and all issuing certificates are assumed to be valid during the leaf certificate\u0027s validity. There is no impact to users of the public Sigstore infrastructure. This may affect private deployments with customized PKIs. This issue has been fixed in version 3.0.5.",
  "id": "UBUNTU-CVE-2026-24122",
  "modified": "2026-07-02T16:11:57Z",
  "published": "2026-02-19T23:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-24122"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-24122"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/sigstore/cosign/commit/3c9a7363f563db76d78e2de2cabd945450f3781e"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/sigstore/cosign/releases/tag/v3.0.5"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/sigstore/cosign/security/advisories/GHSA-wfqv-66vq-46rm"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-24122"
  ]
}

CVE-2026-24122 (GCVE-0-2026-24122)

Vulnerability from cvelistv5 – Published: 2026-02-19 22:27 – Updated: 2026-02-20 15:41

Title

Cosign Certificate Chain Expiry Validation Issue Allows Issuing Certificate Expiry to Be Overlooked

Summary

Severity

3.7 (Low)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-02-20 15:27 UTC

CWE

CWE-295 - Improper Certificate Validation

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/sigstore/cosign/security/advis…	x_refsource_CONFIRM
https://github.com/sigstore/cosign/commit/3c9a736…	x_refsource_MISC
https://github.com/sigstore/cosign/releases/tag/v3.0.5	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
sigstore	cosign	Affected: < 3.0.5

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-24122",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-02-20T15:27:28.783661Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-02-20T15:41:03.939Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "cosign",
          "vendor": "sigstore",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.0.5"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Cosign provides code signing and transparency for containers and binaries. In versions 3.0.4 and below, an issuing certificate with a validity that expires before the leaf certificate will be considered valid during verification even if the provided timestamp would mean the issuing certificate should be considered expired. When verifying artifact signatures using a certificate, Cosign first verifies the certificate chain using the leaf certificate\u0027s \"not before\" timestamp and later checks expiry of the leaf certificate using either a signed timestamp provided by the Rekor transparency log or from a timestamp authority, or using the current time. The root and all issuing certificates are assumed to be valid during the leaf certificate\u0027s validity. There is no impact to users of the public Sigstore infrastructure. This may affect private deployments with customized PKIs. This issue has been fixed in version 3.0.5."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 3.7,
            "baseSeverity": "LOW",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-295",
              "description": "CWE-295: Improper Certificate Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-19T22:27:08.828Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/sigstore/cosign/security/advisories/GHSA-wfqv-66vq-46rm",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/sigstore/cosign/security/advisories/GHSA-wfqv-66vq-46rm"
        },
        {
          "name": "https://github.com/sigstore/cosign/commit/3c9a7363f563db76d78e2de2cabd945450f3781e",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/sigstore/cosign/commit/3c9a7363f563db76d78e2de2cabd945450f3781e"
        },
        {
          "name": "https://github.com/sigstore/cosign/releases/tag/v3.0.5",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/sigstore/cosign/releases/tag/v3.0.5"
        }
      ],
      "source": {
        "advisory": "GHSA-wfqv-66vq-46rm",
        "discovery": "UNKNOWN"
      },
      "title": "Cosign Certificate Chain Expiry Validation Issue Allows Issuing Certificate Expiry to Be Overlooked"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-24122",
    "datePublished": "2026-02-19T22:27:08.828Z",
    "dateReserved": "2026-01-21T18:38:22.473Z",
    "dateUpdated": "2026-02-20T15:41:03.939Z",
    "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.
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.