Cyber Resilience

CVE-2026-44784

Info Disclosure in Discourse ≤ 2026.1.0

Published
12 June 2026
Modified
17 June 2026
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0023 14th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-44784 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Discourse Discourse. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Unsecured Credentials (T1552); ranked at the 14th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.4, 2026.3.0-latest to before 2026.3.1, and 2026.4.0-latest to before 2026.4.1, group owners who are not necessarily admins or moderators can view a group's outgoing email/SMTP credentials in plaintext via…

more

the group history log (/groups/:name/logs.json). Affected fields: email_password, email_username, smtp_server, smtp_port, smtp_ssl_mode. The most sensitive item is the SMTP password, which an owner could use to send mail as the group from outside Discourse. This impacts sites that have configured per-group SMTP credentials and granted group ownership to users who should not have access to those credentials. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
Why these techniques?

Direct exposure of SMTP credentials (incl. plaintext password) to unauthorized group owners via logs enables T1552 Unsecured Credentials.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-33394Same product: Discourse Discourse
CVE-2026-33073Same product: Discourse Discourse
CVE-2026-49256Same product: Discourse Discourse
CVE-2024-53991Same product: Discourse Discourse
CVE-2026-47263Same product: Discourse Discourse
CVE-2026-32099Same product: Discourse Discourse
CVE-2023-23622Same product: Discourse Discourse
CVE-2026-45780Same product: Discourse Discourse
CVE-2024-28242Same product: Discourse Discourse
CVE-2023-45131Same product: Discourse Discourse

Affected Assets

discourse
discourse
2026.5.0 · ≤ 2026.1.0 · 2026.1.0 — 2026.1.4 · 2026.3.0 — 2026.3.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-6 Least Privilege
  • AC-3 Access Enforcement
  • AU-9 Protection of Audit Information
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 7 hardening rules · 6 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V10.4.9
  • V11.7.1
  • V14.1.2
  • V14.2.4

Mitigating Controls (NIST 800-53 r5) AI

prevent

Least privilege directly prevents group owners from being granted access to plaintext SMTP credentials they do not need.

prevent

Access enforcement would block unauthorized retrieval of sensitive credential fields from /groups/:name/logs.json.

prevent

Protection of audit information stops non-privileged users from reading logs that contain plaintext email/SMTP passwords.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

PR.AA-05 directly enforces least-privilege authorization that blocks most unauthorized disclosures, yet CWE-200 also arises from logging, error messages, and side-channel paths that access controls alone do not address.

PR.DS-10 mostly match
prevents

PR.DS-10 mostly prevents CWE-200 by directly eliminating unauthorized access to sensitive data-in-use, yet only partially addresses the weakness because CWE-200 spans many other exposure vectors outside runtime protection.

PR.IR-01 mostly match
prevents

PR.IR-01's segmentation/zero-trust controls largely eliminate network-level unauthorized access paths that enable exposure, yet CWE-200 spans many additional vectors (API responses, logs, app logic) that network controls alone cannot close.

PR.PS-06 mostly match
prevents

Secure SDLC practices catch most exposure flaws via design, testing and release controls, yet CWE-200 spans runtime/config issues a single development outcome cannot fully close.

PR.AA-01 partial match
prevents

PR.AA-01 supplies proper credential lifecycle controls that reduce unauthorized access paths, yet leaves many other exposure vectors (error messages, logging, side channels, etc.) unaddressed.

PR.AA-03 partial match
prevents

Authentication verifies actor identity and is a prerequisite for access decisions, yet addresses only one facet of the broad set of exposure vectors in CWE-200.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Restricting anonymous or unknown access and encrypting high-value information limits the exposure of sensitive data that would otherwise be obtainable by unauthorized actors.

prevents

Suppressing system details, error specifics, and previous log-on information until successful authentication reduces the information an unauthenticated attacker can gather.

prevents

By requiring owners to assign sensitivity labels and corresponding handling rules, the control ensures that information is not left unmarked and therefore reduces the chance that sensitive data will be exposed to unauthorized actors.

prevents

Requiring encryption, access controls, and recipient authentication for transfers directly reduces the chance that sensitive data reaches an unauthorized observer.

prevents

Secure delivery, protected storage, and confidentiality of allocation records limit exposure of authentication material to unauthorized observers.

prevents

Requiring defined procedures, assigned roles, and technical/organizational measures for handling PII reduces the chance that sensitive personal data will be exposed to unauthorized actors through inadequate handling or missing safeguards.

References