Bug 2535577

Summary: CVE-2026-85731 golang-oras-2: oras-go: Arbitrary file write and code execution via symlink-chain bypass [fedora-all]
Product: [Fedora] Fedora Reporter: Vladimir Vasilev <vvasilev>
Component: golang-oras-2Assignee: Orphan Owner <extras-orphan>
Status: NEW --- QA Contact:
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Priority: high    
Version: rawhideCC: extras-orphan, go-sig
Target Milestone: ---Keywords: Security, SecurityTracking
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Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["90fcaa18-4101-4bab-bced-4ab916fd72aa"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On:    
Bug Blocks: 2535549    

Description Vladimir Vasilev 2026-09-16 17:49:05 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.

oras-go is a Go library for managing OCI artifacts. Prior to 2.6.2, content/file.Store extraction of OCI layers marked with io.deis.oras.content.unpack=true can write outside the store working directory. The pushDir path through extractTarDirectory and ensureLinkPath validates symlink targets lexically, resolveRelToBase skips its parent-symlink walk for root-level entries, and writeFile follows a terminal symlink when opening a regular file. A malicious archive can therefore create a symlink chain whose lexical target remains inside the extraction root but whose resolved target is an attacker-selected absolute path, then overwrite that target with a same-named regular-file entry even when AllowPathTraversalOnWrite is false. Pulling an attacker-controlled artifact can create or overwrite any file writable by the process and may lead to code execution. This issue is fixed in version 2.6.2.