CVE-2026-39822: CWE-61: UNIX Symbolic Link (Symlink) Following in Go standard library os
CVE-2026-39822 is a vulnerability in the Go standard library's os package on Unix systems where opening a file with os.Root improperly follows symbolic links that point outside the specified root directory when the path ends with a '/'. This allows access to files outside the intended root directory via symlink traversal. The issue affects specific Go versions including 1.26.0-0, 1.27.0-0, versions before 1.25.12, and versions from 1.26.0-0 up to but not including 1.26.5. No official patch or remediation guidance is currently available. No known exploits in the wild have been reported. The severity is assessed as medium due to the potential for unauthorized file access but limited details on exploitation impact.
AI Analysis
Technical Summary
On Unix systems, the Go standard library's os package has a vulnerability (CVE-2026-39822) where the os.Root function improperly follows symbolic links when the final path component is a symlink and the path ends with a '/'. This behavior allows opening files outside the intended root directory by following symlinks that point elsewhere. The affected versions include exactly 1.26.0-0, 1.27.0-0, all versions before 1.25.12, and versions from 1.26.0-0 up to but excluding 1.26.5. There is no CVSS score or vendor advisory indicating a patch or workaround. The vulnerability is categorized under CWE-61 (Improper Restriction of Symbolic Links).
Potential Impact
This vulnerability can lead to unauthorized file access outside the intended root directory when using os.Root on Unix systems, potentially exposing sensitive files or data. The impact depends on how the os package is used in applications and whether attackers can control or influence the symlink paths. No known exploits have been reported, so the real-world impact is currently unknown.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should carefully validate and sanitize paths and avoid relying solely on os.Root for security boundaries involving symbolic links. Monitor official Go project communications for updates on patches or workarounds.
CVE-2026-39822: CWE-61: UNIX Symbolic Link (Symlink) Following in Go standard library os
Description
CVE-2026-39822 is a vulnerability in the Go standard library's os package on Unix systems where opening a file with os.Root improperly follows symbolic links that point outside the specified root directory when the path ends with a '/'. This allows access to files outside the intended root directory via symlink traversal. The issue affects specific Go versions including 1.26.0-0, 1.27.0-0, versions before 1.25.12, and versions from 1.26.0-0 up to but not including 1.26.5. No official patch or remediation guidance is currently available. No known exploits in the wild have been reported. The severity is assessed as medium due to the potential for unauthorized file access but limited details on exploitation impact.
Affected software
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
On Unix systems, the Go standard library's os package has a vulnerability (CVE-2026-39822) where the os.Root function improperly follows symbolic links when the final path component is a symlink and the path ends with a '/'. This behavior allows opening files outside the intended root directory by following symlinks that point elsewhere. The affected versions include exactly 1.26.0-0, 1.27.0-0, all versions before 1.25.12, and versions from 1.26.0-0 up to but excluding 1.26.5. There is no CVSS score or vendor advisory indicating a patch or workaround. The vulnerability is categorized under CWE-61 (Improper Restriction of Symbolic Links).
Potential Impact
This vulnerability can lead to unauthorized file access outside the intended root directory when using os.Root on Unix systems, potentially exposing sensitive files or data. The impact depends on how the os package is used in applications and whether attackers can control or influence the symlink paths. No known exploits have been reported, so the real-world impact is currently unknown.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should carefully validate and sanitize paths and avoid relying solely on os.Root for security boundaries involving symbolic links. Monitor official Go project communications for updates on patches or workarounds.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Go
- Date Reserved
- 2026-04-07T18:13:03.527Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4e7ad4c9d9e3dbe36a7d51
Added to database: 07/08/2026, 16:29:08 UTC
Last enriched: 07/08/2026, 16:44:38 UTC
Last updated: 07/08/2026, 23:04:37 UTC
Views: 6
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.