Vulnerability · Published Mar 6, 2026 · Assigned by Go

CVE-2026-27139FileInfo can escape from a Root in os

Low 2.5

In plain English

A low-severity security flaw in os from Go standard library. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 12% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)2.5Low
Exploit odds (30 days)0.2%top 87.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

On Unix platforms, when listing the contents of a directory using File.ReadDir or File.Readdir the returned FileInfo could reference a file outside of the Root in which the File was opened. The impact of this escape is limited to reading metadata provided by lstat from arbitrary locations on the filesystem without permitting reading or writing files outside the root.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.23go1.25.8-r0ALPINE-CVE-2026-27139
Alpine:v3.24go1.25.8-r0ALPINE-CVE-2026-27139
Debian:12golang-1.19no fix listedDEBIAN-CVE-2026-27139
Debian:13golang-1.24no fix listedDEBIAN-CVE-2026-27139
Debian:14golang-1.261.26.1-1DEBIAN-CVE-2026-27139
Gostdlib1.25.8, 1.26.1GO-2026-4602
Ubuntu:22.04:LTSgolang-1.24no fix listedUBUNTU-CVE-2026-27139
Ubuntu:24.04:LTSgolang-1.24no fix listedUBUNTU-CVE-2026-27139
Ubuntu:25.10golang-1.24no fix listedUBUNTU-CVE-2026-27139
Ubuntu:26.04:LTSgolang-1.24no fix listedUBUNTU-CVE-2026-27139
Ubuntu:22.04:LTSgolang-1.25no fix listedUBUNTU-CVE-2026-27139
Ubuntu:24.04:LTSgolang-1.25no fix listedUBUNTU-CVE-2026-27139
Ubuntu:25.10golang-1.25no fix listedUBUNTU-CVE-2026-27139
Ubuntu:26.04:LTSgolang-1.25no fix listedUBUNTU-CVE-2026-27139
Ubuntu:22.04:LTSgolang-1.26no fix listedUBUNTU-CVE-2026-27139
Ubuntu:24.04:LTSgolang-1.26no fix listedUBUNTU-CVE-2026-27139
Ubuntu:26.04:LTSgolang-1.26no fix listedUBUNTU-CVE-2026-27139
Ubuntu:26.10golang-1.26no fix listedUBUNTU-CVE-2026-27139

Affected products (as reported)

VendorProductVersions
Go standard library os 0 – before 1.25.81.26.0-0 – before 1.26.1

References