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Fencer Vulns
low 3.7

CVE-2026-24122 json

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

published 2026-02-19 8 mo ago modified 2026-09-10 1 mo ago also BIT-cosign-2026-24122 , EUVD-2026-8430 , GHSA-wfqv-66vq-46rm , GO-2026-4529

cvss
3.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 12%
public exploits
0
none known

Summary

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.

Patch / fix

  • go github.com/sigstore/cosign 3.0.5
  • bitnami cosign 3.0.5
  • go github.com/sigstore/cosign/v3 3.0.5
  • sigstore cosign 3.0.5
  • cosign Debian 14 3.0.6-1

debian advisories DEBIAN-CVE-2026-24122

  • cosign SLES for SAP applications 16.0, SLES 16.0 3.0.5-160000.1.1
  • cosign SLE Module for Basesystem 15 SP7, openSUSE Leap 15.6 3.0.5-150400.3.35.1
  • govulncheck-vulndb openSUSE Leap 15.6 0.0.20260226T182644-150000.1.149.1

suse advisories SUSE-SU-2026:20904-1SUSE-SU-2026:0777-1SUSE-SU-2026:0757-1

  • trivy openSUSE Leap 16.0 0.74.0-160000.2.1
  • trivy openSUSE Tumbleweed 0.74.0-2.1
  • govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
  • hauler openSUSE Tumbleweed 1.4.2-1.1
  • cosign openSUSE Leap 16.0 3.0.5-160000.1.1
  • cosign openSUSE Tumbleweed 3.0.5-1.1

opensuse advisories openSUSE-SU-2026:21801-1openSUSE-SU-2026:11676-1openSUSE-SU-2026:21483-1openSUSE-SU-2026:10635-1openSUSE-SU-2026:20386-1openSUSE-SU-2026:10235-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-24122 updated cvss 3.7

sigstore/cosign: sigstore/cosign: Incorrect signature validation due to expired issuing certificate bypass

  • Red Hat External Secrets Operator for Red Hat OpenShift external-secrets-operator/external-secrets-rhel9, external-secrets-operator/bitwarden-sdk-server-rhel9, external-secrets-operator/external-secrets-operator-rhel9, external-secrets-operator/external-secrets-operator-bundle Red Hat OpenShift Pipelines openshift-pipelines-client, openshift-pipelines/pipelines-opc-rhel9, openshift-pipelines/pipelines-cli-tkn-rhel8, openshift-pipelines/pipelines-cli-tkn-rhel9, openshift-pipelines/pipelines-git-init-rhel8, openshift-pipelines/pipelines-rhel8-operator, +6 more Red Hat OpenShift Serverless openshift-serverless-1/kn-plugin-event-sender-rhel9 Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/acm-prometheus-rhel9, rhacm2/acm-prometheus-config-reloader-rhel9 Red Hat Advanced Cluster Security 4 advanced-cluster-security/rhacs-main-rhel8, advanced-cluster-security/rhacs-roxctl-rhel8, advanced-cluster-security/rhacs-rhel8-operator, advanced-cluster-security/rhacs-scanner-v4-rhel8 Red Hat OpenShift AI (RHOAI) rhoai/odh-model-registry-rhel9, rhoai/odh-data-science-pipelines-argo-argoexec-rhel8, rhoai/odh-data-science-pipelines-argo-workflowcontroller-rhel8
    +6 more products
    Red Hat OpenShift Container Platform 4 openshift4/cnf-tests-rhel9, openshift4/ztp-site-generate-rhel8 Red Hat Satellite 6 satellite/iop-vmaas-rhel9, satellite/iop-puptoo-rhel9, satellite/iop-yuptoo-rhel9, satellite/iop-gateway-rhel9, satellite/iop-ingress-rhel9, satellite/iop-remediations-rhel9, +6 more Red Hat Trusted Artifact Signer rhtas/cosign-rhel9, rhtas/fulcio-rhel9, rhtas/gitsign-rhel9, rhtas/rekor-cli-rhel9, rhtas/rekor-server-rhel9, rhtas/client-server-rhel9, +3 more Red Hat Security Profiles Operator compliance/openshift-security-profiles-rhel8-operator, compliance/openshift-security-profiles-operator-bundle Red Hat Zero Trust Workload Identity Manager zero-trust-workload-identity-manager/spiffe-spire-agent-rhel9, zero-trust-workload-identity-manager/spiffe-spire-server-rhel9, zero-trust-workload-identity-manager/spiffe-spire-oidc-discovery-provider-rhel9 Red Hat Zero Trust Workload Identity Manager - Tech Preview zero-trust-workload-identity-manager/spiffe-spire-agent-rhel9, zero-trust-workload-identity-manager/spiffe-spire-server-rhel9, zero-trust-workload-identity-manager/spiffe-spire-oidc-discovery-provider-rhel9, zero-trust-workload-identity-manager/zero-trust-workload-identity-manager-rhel9, zero-trust-workload-identity-manager/zero-trust-workload-identity-manager-operator-bundle
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
8 mo ago

Exploit prediction

0.21% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/sigstore/cosign/security/advisories/GHSA-wfqv-66vq-46rm referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
GitHub 3.1 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
OSV 3.1 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected packages

ecosystem package affected fixed in
go github.com/sigstore/cosign
<3.0.5
all versions
3.0.5
bitnami cosign
<3.0.5
3.0.5
go github.com/sigstore/cosign/v2
all versions
 no fix listed
go github.com/sigstore/cosign/v3
<3.0.5
3.0.5

Affected products

  • sigstore cosign

Classification

Weakness
  • CWE-295 Improper Certificate Validation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.