CVE-2026-44787

Status: AnalyzedHigh (7.1)—

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, the signup flow could allow newly registered users to set primary_group_id and gain whisper-group privileges without legitimate group membership on sites with whispers_allowed_groups configured. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
Base score: 7.1

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.46%
Percentile among all scored CVEs: 38
Score date: 10/6/2026

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.

ExploitationT1210 Exploitation of Remote Serviceslateral movement75 %
Primary impactT1068 Exploitation for Privilege Escalationprivilege escalation80 %
Secondary impactT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access70 %

Acceso remoto con PR:L que permite escalada de privilegios mediante manipulación de parámetros (primary_group_id) en el flujo de registro. Requiere autenticación previa para ganar privilegios de grupo sin membresía legítima.

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

Threat Intelligence Program Application Isolation and Sandboxing Exploit Protection Update Software Vulnerability Scanning Privileged Account Management

Affected technologies (1)

Discourse — Discourse

CWEs

CWE-269

References

Raw JSON (NVD)

Show

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