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CVE-2026-27154

Status: AnalyzedLow (1.3)—

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, a user full name can be evaluated as raw HTML when the following settings are set: `display_name_on_posts` => true; and `prioritize_username_in_ux` => false. Editing a post of a malicious user would trigger an XSS. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.

CVSS

Exploitation probability (EPSS)

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).

Affected technologies (1)

Discourse — Discourse

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-27154",
  "cveTags": [],
  "metrics": {
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        "ssvcData": {
          "id": "CVE-2026-27154",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-03-02T20:56:42.809375Z"
        }
      }
    ],
    "cvssMetricV31": [
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        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
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          "version": "3.1",
          "baseScore": 6.1,
          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
          "integrityImpact": "LOW",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "LOW"
        },
        "impactScore": 2.7,
        "exploitabilityScore": 2.8
      }
    ],
    "cvssMetricV40": [
      {
        "type": "Secondary",
        "source": "security-advisories@github.com",
        "cvssData": {
          "Safety": "NOT_DEFINED",
          "version": "4.0",
          "Recovery": "NOT_DEFINED",
          "baseScore": 1.3,
          "Automatable": "NOT_DEFINED",
          "attackVector": "NETWORK",
          "baseSeverity": "LOW",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "exploitMaturity": "UNREPORTED",
          "providerUrgency": "NOT_DEFINED",
          "userInteraction": "NONE",
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          "attackRequirements": "NONE",
          "privilegesRequired": "LOW",
          "subIntegrityImpact": "LOW",
          "vulnIntegrityImpact": "NONE",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "vulnAvailabilityImpact": "NONE",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "LOW",
          "vulnConfidentialityImpact": "NONE",
          "confidentialityRequirement": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
        }
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      "affectedData": [
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          "vendor": "discourse",
          "product": "discourse",
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              "version": "< 2025.12.2"
            },
            {
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              "version": ">= 2026.1.0-latest, < 2026.1.1"
            },
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              "status": "affected",
              "version": ">= 2026.2.0-latest, < 2026.2.0"
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  ],
  "published": "2026-02-26T22:20:47.730",
  "references": [
    {
      "url": "https://github.com/discourse/discourse/security/advisories/GHSA-xv43-5gcp-wgw8",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, a user full name can be evaluated as raw HTML when the following settings are set: `display_name_on_posts` => true; and `prioritize_username_in_ux` => false. Editing a post of a malicious user would trigger an XSS. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available."
    },
    {
      "lang": "es",
      "value": "Discourse es una plataforma de discusión de código abierto. Antes de las versiones 2025.12.2, 2026.1.1 y 2026.2.0, el nombre completo de un usuario puede ser evaluado como HTML sin procesar cuando las siguientes configuraciones están establecidas: 'display_name_on_posts' =&gt; true; y 'prioritize_username_in_ux' =&gt; false. Editar una publicación de un usuario malicioso activaría un XSS. Las versiones 2025.12.2, 2026.1.1 y 2026.2.0 parchean el problema. No hay soluciones alternativas conocidas disponibles."
    }
  ],
  "lastModified": "2026-06-17T10:26:46.323",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
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              "versionEndExcluding": "2025.12.2"
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              "vulnerable": true,
              "matchCriteriaId": "1CAFCC9D-53D7-4017-85A5-EE6CA5A6A11C",
              "versionEndExcluding": "2026.1.1",
              "versionStartIncluding": "2026.1.0"
            },
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              "matchCriteriaId": "BB002FDC-BC71-4C46-8AAF-A34EC717E0E7"
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}