CVE-2026-4858 (GCVE-0-2026-4858)

Vulnerability from cvelistv5 – Published: 2026-05-21 08:12 – Updated: 2026-05-21 12:10
VLAI?
Title
Path traversal in integration action URL leading to arbitrary API execution via system admin’s auth token.
Summary
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to check integration URL for path traversal which allows an malicious authenticated user to call an arbitrary API via system admin Mattermost auth token using via path traversal in integration action URL.. Mattermost Advisory ID: MMSA-2026-00640
Severity ?
8 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version
Mattermost Mattermost Affected: 11.6.0 , ≤ 11.6.0 (semver)
Affected: 11.5.0 , ≤ 11.5.3 (semver)
Affected: 11.4.0 , ≤ 11.4.4 (semver)
Affected: 10.11.0 , ≤ 10.11.14 (semver)
Unaffected: 11.7.0
Unaffected: 11.6.1
Unaffected: 11.5.4
Unaffected: 11.4.5
Unaffected: 10.11.15
Create a notification for this product.
Credits
daw10
Show details on NVD website
To clipboard 

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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

Author Source Type Date Other

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.