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CVE-2026-26986 (GCVE-0-2026-26986)

Vulnerability from cvelistv5 – Published: 2026-02-25 21:01 – Updated: 2026-02-26 20:36
VLAI
Title
FreeRDP has heap-use-after-free in rail_window_free
Summary
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, `rail_window_free` dereferences a freed `xfAppWindow` pointer during `HashTable_Free` cleanup because `xf_rail_window_common` calls `free(appWindow)` on title allocation failure without first removing the entry from the `railWindows` hash table, leaving a dangling pointer that is freed again on disconnect. Version 3.23.0 fixes the vulnerability.
Severity
5.5 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-26 20:35 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
FreeRDP FreeRDP Affected: < 3.23.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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          "value": "FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.23.0, `rail_window_free` dereferences a freed `xfAppWindow` pointer during `HashTable_Free` cleanup because `xf_rail_window_common` calls `free(appWindow)` on title allocation failure without first removing the entry from the `railWindows` hash table, leaving a dangling pointer that is freed again on disconnect. Version 3.23.0 fixes the vulnerability."
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-06-28T07:22:51+00:00",
      "cve": "CVE-2026-26986",
      "id": "CVE-2026-26986",
      "initial_release_date": "2026-02-25T21:01:16.916000+00:00",
      "product_status:fixed": "781",
      "product_status:known_affected": "5",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "freerdp: FreeRDP: Denial of Service via double free vulnerability during disconnect",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26986.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-06-25T02:26:52Z",
      "cve": "CVE-2026-26986",
      "id": "CVE-2026-26986",
      "initial_release_date": "2026-02-28T00:24:40Z",
      "product_status:known_affected": "27",
      "product_status:recommended": "116",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-26986",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-26986.json",
      "version": "7"
    }
  }
}



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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.


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