oras-go: Arbitrary file write outside file.Store root via symlink-chain bypass in tar extraction (pushDir) (CVE-2026-85731) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-85731

oras-go: Arbitrary file write outside file.Store root via symlink-chain bypass in tar extraction (pushDir)

Answer in brief

CVE-2026-85731 records a Unknown severity vulnerability in oras-go: Arbitrary file write outside file.Store root via symlink-chain bypass in tar extraction (pushDir). The current sources do not mark it as known exploited. The current feed maps oras-project/oras-go (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 16, 2026Updated Sep 16, 2026Source checked Sep 16, 2026First seen by HOL Sep 16, 2026Material review Sep 16, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps oras-project/oras-go (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
oras-project/oras-gogeneric	< 2.6.2	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for oras-project/oras-go.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 16, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.