PT-2026-26361 · Discourse · Discourse

Nlgbao1340 · Publicado 2026-03-19 · Atualizado 2026-04-10 · CVE-2026-27740

Positive Technologies (AI Summary)

CVSS v3.1

6.1

Média

Vetor base

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 2026.3.0-latest.1 Discourse versions prior to 2026.2.1 Discourse versions prior to 2026.1.2

Description Discourse, an open-source discussion platform, is affected by a cross-site scripting issue. The system improperly trusts and renders output from an AI Large Language Model (LLM) using htmlSafe within the Review Queue interface, lacking sufficient sanitization. An attacker can leverage Prompt Injection techniques to make the AI generate a malicious payload, such as tags. When a staff member (Admin/Moderator) views a flagged post in the Review Queue, this payload is executed.

Recommendations Versions prior to 2026.3.0-latest.1 should be updated. Versions prior to 2026.2.1 should be updated. Versions prior to 2026.1.2 should be updated. As a temporary workaround, disable AI triage automation scripts.

Exploit

Correção

XSS

Enumeração de Fraquezas

CWE-79

Identificadores relacionados

BIT-DISCOURSE-2026-27740

CVE-2026-27740

GHSA-95HC-42C6-WVVR

Produtos afetados

Discourse

Referências · 13

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27740.json · Exploit
• https://github.com/discourse/discourse/commit/ed70949f2c047196f33cfa94f2819df29c5d1e5f · Correção
• https://github.com/discourse/discourse/commit/44b84439df7e4424b2e7f216fd8fdd7dacff2227 · Correção
• https://github.com/discourse/discourse/security/advisories/GHSA-95hc-42c6-wvvr · Aviso do Fabricante
• https://github.com/discourse/discourse/commit/8ae7cb2414d6918d7fc45e1fda7ffbb32912a975 · Correção
• https://twitter.com/ai_security_10x/status/2035675843532595440 · Publicação no Twitter
• https://twitter.com/CVEnew/status/2035627054696218801 · Publicação no Twitter
• https://nvd.nist.gov/vuln/detail/CVE-2026-27740 · Nota de Segurança
• https://osv.dev/vulnerability/BIT-discourse-2026-27740 · Aviso do Fabricante
• https://twitter.com/CisoRaging77913/status/2042482964731203707 · Publicação no Twitter
• https://twitter.com/VulmonFeeds/status/2034810851115340214 · Publicação no Twitter
• https://twitter.com/infoflowcloud/status/2035627843015660020 · Publicação no Twitter
• https://osv.dev/vulnerability/CVE-2026-27740 · Aviso do Fabricante