REDHAT-BUG-2419056: High severity Fulcio Fulcio vulnerability

Published Dec 4, 2025
·
Updated

Fulcio is a free-to-use certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Prior to 1.8.3, function identity.extractIssuerURL splits (via a call to strings.Split) its argument (which is untrusted data) on periods. As a result, in the face of a malicious request with an (invalid) OIDC identity token in the payload containing many period characters, a call to extractIssuerURL incurs allocations to the tune of O(n) bytes (where n stands for the length of the function's argument), with a constant factor of about 16. This vulnerability is fixed in 1.8.3.

Affected Software

1 affected component
Fulcio Fulcio<1.8.3

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Fulcio to a version that resolves this vulnerability.

    Fixed in 1.8.3

Event History

Dec 4, 2025
Data Sourced
via Red Hat·11:02 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2419056?

The severity of REDHAT-BUG-2419056 is classified as high with a score of 7.

2

What are the potential impacts of REDHAT-BUG-2419056?

REDHAT-BUG-2419056 can lead to security vulnerabilities due to improper handling of untrusted data, potentially allowing for malicious exploitation.

3

How do I fix REDHAT-BUG-2419056?

To fix REDHAT-BUG-2419056, upgrade to Fulcio version 1.8.3 or later, where the vulnerability has been addressed.

4

What software is affected by REDHAT-BUG-2419056?

The affected software for REDHAT-BUG-2419056 is Fulcio.

5

Why is REDHAT-BUG-2419056 considered a risk?

REDHAT-BUG-2419056 is considered a risk because it exposes the system to potential unauthorized access through code signing vulnerabilities.

Contact

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