Bug 2558235

Summary: CVE-2026-56864 golang-x-mod: golang.org/x/mod/sumdb: Integrity bypass via malicious GOSUMDB [epel-all]
Product: [Fedora] Fedora EPEL Reporter: Yadnyawalk Tale <ytale>
Component: golang-x-modAssignee: Mark E. Fuller <mark.e.fuller>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: epel10CC: epel-packagers-sig, go-sig, mark.e.fuller
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["e627c00c-1f06-459a-b10e-1e64e58d574f"]}
Fixed In Version: Doc Type: ---
Doc Text:
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Clone Of: Environment:
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Regression: --- Mount Type: ---
Documentation: --- CRM:
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2515836    

Description Yadnyawalk Tale 2026-10-21 12:00:10 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

A malicious GOSUMDB was capable of serving arbitrary module content not contained within the transparency log. This attack allows for a coordinating GOPROXY and GOSUMDB to serve a client malicious module content that cannot be detected by evaluating the transparency log. In order to determine if you have been affected:   rm -r go.sum go.work.sum vendor/ && go mod tidy