CVE-2026-39822 | BDVDB-2026-346199 Detail

Go standard libraryos

Description#

On Unix systems, opening a file in an os.Root improperly follows symlinks to locations outside of the Root when the final path component of the a path is a symbolic link and the path ends in /. For example, 'root.Open("symlink/")' will open "symlink" even when "symlink" is a symbolic link pointing outside of the root.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: local.

Weaknesses#

CWE-61 UNIX Symbolic Link (Symlink) Following

References#

Exploit#

No public exploit known

History#

Version 12026-07-08Record published in the CVE List.

Published

Published: 2026-07-08
Last modified: 2026-07-08

Vendor information

Vendor: Go standard library
Product: os

All Go standard library vulnerabilities

Score

7.8 High

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 14.2.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 1.25.12
Fixed
1.25.12
Vulnerable
>= 1.26.0-0 and < 1.26.5
Fixed
1.26.5
Vulnerable
>= 1.27.0-0 and < 1.27.0-rc.2
Fixed
1.27.0-rc.2

Scoring System

CVSS v4.0

Not available

CVSS v3.1

7.8 High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Metric breakdown
Attack Vector	Local
Attack Complexity	Low
Privileges Required	Low
User Interaction	None
Scope	Unchanged
Confidentiality	High
Integrity	High
Availability	High

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).