CVE-2026-107612

Status: Awaiting AnalysisHigh (7.8)—

Incorrect permission assignment in GlavSoft TightVNC Server for Windows before 2.8.88 allows a local authenticated user to read or overwrite the inter-process communication handles used between the TightVNC service and its desktop server process. The named shared memory segment in the Global\ namespace that carries the pipe HANDLE values is created with a NULL DACL, and its name is derived from a time-seeded srand(time(0)) value that is predictable to one-second granularity. A low-privileged local process can open the mapping and tamper with the IPC channel of a service running as SYSTEM, potentially leading to disclosure of session data, privilege escalation, or denial of service.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.10%
Percentile among all scored CVEs: 1
Score date: 10/13/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1068 Exploitation for Privilege Escalationprivilege escalation95 %
Primary impactT1222 File and Directory Permissions Modificationdefense impairment90 %
Secondary impactT1005 Data from Local Systemcollection85 %
Secondary impactT1548 Abuse Elevation Control Mechanismprivilege escalation80 %

Vulnerabilidad de asignación incorrecta de permisos (NULL DACL) en IPC de servicio SYSTEM. Acceso local autenticado (AV:L, PR:L) sin interacción permite lectura/sobrescritura de handles. Impactos: modificación de permisos (T1222), acceso a datos de sesión (T1005), y escalada de privilegios (T1548).

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Restrict File and Directory Permissions Privileged Account Management Execution Prevention Update Software User Account Management Threat Intelligence Program

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Glavsoft — Tightvnc Server^AI

CWEs

CWE-338, CWE-732

References

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-107612",
  "cveTags": [],
  "metrics": {
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-107612",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-08T14:01:50.062814Z"
        }
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          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
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        "impactScore": 5.9,
        "exploitabilityScore": 1.8
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  "affected": [
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      "source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c",
      "affectedData": [
        {
          "vendor": "GlavSoft",
          "modules": [
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          ],
          "product": "TightVNC",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "2.8.88",
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          "platforms": [
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          "programFiles": [
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          "programRoutines": [
            {
              "name": "DesktopServerWatcher::execute()"
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  "published": "2026-10-08T14:16:49.877",
  "references": [
    {
      "url": "https://sourceforge.net/p/vnc-tight/bugs/1658/",
      "source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c"
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      "description": [
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  "descriptions": [
    {
      "lang": "en",
      "value": "Incorrect permission assignment in GlavSoft TightVNC Server for Windows before 2.8.88 allows a local authenticated user to read or overwrite the inter-process communication handles used between the TightVNC service and its desktop server process. The named shared memory segment in the Global\\ namespace that carries the pipe HANDLE values is created with a NULL DACL, and its name is derived from a time-seeded srand(time(0)) value that is predictable to one-second granularity. A low-privileged local process can open the mapping and tamper with the IPC channel of a service running as SYSTEM, potentially leading to disclosure of session data, privilege escalation, or denial of service."
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  "lastModified": "2026-10-08T21:10:00.133",
  "sourceIdentifier": "33c584b5-0579-4c06-b2a0-8d8329fcab9c"
}