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Fencer Intel
high 8.8

CVE-2026-85731 json

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

published last mo. modified last mo. also EUVD-2026-80873 , GHSA-m37j-52j7-pjw7 , GO-2026-6499

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits
0
none known

Summary

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.

Patch / fix

  • go oras.land/oras-go/v2 2.6.2
  • linuxfoundation oras 2.6.2
  • golang-oras-oras-go Debian 14 2.6.2-1

debian advisories DEBIAN-CVE-2026-85731

  • helm SLES for SAP 15 SP6, SLES for SAP 15 SP5, SLES for SAP 15 SP4 +10 more 3.22.0-150000.1.99.1

suse advisories SUSE-SU-2026:4417-1

  • helm3 openSUSE Tumbleweed 3.22.0-1.1

opensuse advisories openSUSE-SU-2026:11832-1

Is CVE-2026-85731 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-85731 updated cvss 8.8

github.com/oras-project/oras-go: oras-go: Arbitrary file write and code execution via symlink-chain bypass

  • Red Hat OpenShift AI (RHOAI) rhoai/odh-ai-gateway-operator-rhel9, rhoai/odh-ogx-module-operator-rhel9, rhoai/odh-kserve-module-operator-rhel9
    affected: workaround, no fix available

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
total
Assessed
last mo.

Exploit prediction

0.68% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-11).

Exploits and checks

  • github.com https://github.com/oras-project/oras-go/security/advisories/GHSA-m37j-52j7-pjw7 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
GitHub 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
go oras.land/oras-go/v2
<2.6.2
2.6.2

Affected products

  • oras-project oras-go

Classification

Weakness
  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory
  • CWE-59 Improper Link Resolution Before File Access

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.