CVE-2026-39817: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in Go toolchain cmd/go
CVE-2026-39817 is a medium-severity path traversal vulnerability in the Go toolchain's cmd/go component, specifically affecting the 'go tool pack' subcommand. This flaw allows a malicious archive to write files to arbitrary filesystem locations due to improper sanitization of output filenames when extracting archives. It affects Go versions up to 1.26.0-0. There is currently no official patch or remediation guidance available, and no known exploits have been reported in the wild.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-39817) involves improper limitation of a pathname to a restricted directory (CWE-22) in the Go toolchain's cmd/go 'go tool pack' subcommand. When extracting archives, the tool does not properly sanitize output filenames, enabling a crafted archive to write files outside the intended directory, potentially overwriting arbitrary files. The issue affects Go versions up to and including 1.26.0-0. No official fix or remediation guidance has been published, and no exploitation in the wild is known.
Potential Impact
An attacker who can supply a malicious archive to the 'go tool pack' subcommand may cause files to be written to arbitrary locations on the filesystem. This can lead to integrity violations by overwriting or creating files outside the intended extraction directory. The vulnerability does not impact confidentiality or availability directly. The CVSS score of 5.9 reflects a medium severity with local attack vector, low complexity, requiring low privileges and user interaction, and a scope change with impact on integrity only.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should exercise caution when extracting archives with the 'go tool pack' subcommand, especially from untrusted sources. Avoid processing untrusted archives to mitigate risk.
CVE-2026-39817: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in Go toolchain cmd/go
Description
CVE-2026-39817 is a medium-severity path traversal vulnerability in the Go toolchain's cmd/go component, specifically affecting the 'go tool pack' subcommand. This flaw allows a malicious archive to write files to arbitrary filesystem locations due to improper sanitization of output filenames when extracting archives. It affects Go versions up to 1.26.0-0. There is currently no official patch or remediation guidance available, and no known exploits have been reported in the wild.
CVSS v3.1
Score 5.9medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-39817) involves improper limitation of a pathname to a restricted directory (CWE-22) in the Go toolchain's cmd/go 'go tool pack' subcommand. When extracting archives, the tool does not properly sanitize output filenames, enabling a crafted archive to write files outside the intended directory, potentially overwriting arbitrary files. The issue affects Go versions up to and including 1.26.0-0. No official fix or remediation guidance has been published, and no exploitation in the wild is known.
Potential Impact
An attacker who can supply a malicious archive to the 'go tool pack' subcommand may cause files to be written to arbitrary locations on the filesystem. This can lead to integrity violations by overwriting or creating files outside the intended extraction directory. The vulnerability does not impact confidentiality or availability directly. The CVSS score of 5.9 reflects a medium severity with local attack vector, low complexity, requiring low privileges and user interaction, and a scope change with impact on integrity only.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should exercise caution when extracting archives with the 'go tool pack' subcommand, especially from untrusted sources. Avoid processing untrusted archives to mitigate risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Go
- Date Reserved
- 2026-04-07T18:13:03.524Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fcf0c1cbff5d86102bd5b9
Added to database: 05/07/2026, 20:06:25 UTC
Last enriched: 06/24/2026, 17:19:21 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 104
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