Skip to main content
HIGH

CVE-2026-49478

CVSS v3

8.7

HIGH

EPSS Score

0.3 %

exploit probability, as of 2026-10-19

CISA KEV

No

known exploited

Exploitation

—

SSVC status

Get an alert for each new CVE published for sigstore/fulcio.

Set up CVE WatchFree account · no credit card

Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • github.com/sigstore/fulcioGoall versions · fixed in 1.8.6

Vendor advisories

  • CVE-2026-49478 Red Hat Product Security8 products fixed · 163 known affected

    github.com/sigstore/fulcio: Fulcio: Server-Side Request Forgery and Kubernetes ServiceAccount token leakage

    assisted/agent-preinstall-image-builder-rhel9 as a component of Assisted Installer for Red Hat OpenShift Container Platform 2 · openshift-sandboxed-containers/osc-must-gather-rhel9 as a component of Confidential Compute Attestation · kmm/kernel-module-management-must-gather-rhel9 as a component of Kernel Module Management Operator for Red Hat Openshift

  • RHSA-2026:48913 Red Hat Product Security4 products fixed

    Red Hat Security Advisory: RHACS 4.10.6 security and bug fix update

  • RHSA-2026:48872 Red Hat Product Security4 products fixed

    Red Hat Security Advisory: RHACS 4.9.10 security and bug fix update

Full record on NVD

Description

Fulcio is a certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Versions through 1.8.5 improperly follow cross-host redirects and attach Kubernetes ServiceAccount tokens during OIDC discovery, allowing a malicious or compromised issuer to perform blind SSRF, substitute and cache malicious JWKS keys, or disclose ServiceAccount tokens to external hosts. Version 1.8.6 blocks cross-host redirects, restricts token injection, and restricts local token loading. No known workarounds are available.

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
Published
2026-08-13
Last Modified
2026-08-15

Frequently asked questions

What is CVE-2026-49478?

Fulcio is a certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Versions through 1.8.5 improperly follow cross-host redirects and attach Kubernetes ServiceAccount tokens during OIDC discovery, allowing a malicious or compromised issuer to perform blind SSRF, substitute and cache malicious JWKS keys, or disclose ServiceAccount tokens to external hosts. Version 1.8.6 blocks cross-host redirects, restricts token injection, and restricts local token loading. No known workarounds are available.

Is CVE-2026-49478 actively exploited?

Active exploitation of CVE-2026-49478 has not been confirmed. Its EPSS score was 0.3% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-49478?

CVE-2026-49478 has a CVSS v3 base score of 8.7 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N.

Running sigstore/fulcio? Hear about its next vulnerability

CVE Watch matches each new CVE to the vendors and products you list (vendor and product, not the version) and puts it in your alerts with its KEV and EPSS status.

Get alerts for this productCISA KEV additions, October 2026Search CVEs

Already have an account? Open CVE WatchNo credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database