CVE-2026-39822 (GCVE-0-2026-39822)

Vulnerability from cvelistv5 – Published: 2026-07-08 15:46 – Updated: 2026-07-08 19:39
VLAI
Title
Root escape via symlink plus trailing slash in os
Summary
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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-08 18:06 UTC
CWE
  • CWE-61 - UNIX Symbolic Link (Symlink) Following
Assigner
References
Impacted products
Vendor Product Version CPE status
Go standard library os Affected: 0 , < 1.25.12 (semver)
Affected: 1.26.0-0 , < 1.26.5 (semver)
Affected: 1.27.0-0 , < 1.27.0-rc.2 (semver)
guessed Create a notification for this product.
Credits
Mundur (https://github.com/M0nd0R)
Show details on NVD website
To clipboard 

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      "title": "golang: Go os.Root: Symlink following vulnerability allows directory traversal",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.