Bug 2521822

Summary: CVE-2026-8933 snapd: snap-confine: Local Privilege Escalation via Insecure Privilege Boundary Initialization [epel-all]
Product: [Fedora] Fedora EPEL Reporter: Vladimir Vasilev <vvasilev>
Component: snapdAssignee: Zygmunt Krynicki <me>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: epel10CC: ales.astone, go-sig, maciek.borzecki, me, ngompa13
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["1922a27f-78d8-427a-8207-2224a027a747"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On:    
Bug Blocks: 2503663    

Description Vladimir Vasilev 2026-08-24 11:38:44 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 local privilege escalation vulnerability exists in snap-confine, a set-capabilities core component used internally by Canonical snapd to construct the secure execution environment for snap applications. This vulnerability uniquely affects versions of snap-confine configured with set-capabilities (rather than standard set-uid-root installations).
Due to a flaw in how privilege boundaries or security sandboxes are initialized when the binary runs under limited ambient capabilities, a local, unprivileged attacker can exploit this behavior to bypass intended restrictions and execute arbitrary code. Successful exploitation allows the local user to elevate their privileges to full root authority.