CVE-2026-23630

Published Jan 21, 2026

Last updated 6 months ago

Overview

AI description

Automated description summarized from trusted sources.

CVE-2026-23630 identifies a stored Cross-Site Scripting (XSS) vulnerability within Docmost, an open-source collaborative wiki and documentation software. This flaw affects Docmost versions 0.3.0 through 0.23.2. The vulnerability stems from the application's handling of Mermaid code block rendering, where attacker-controlled Mermaid diagrams are processed and then directly inserted into the Document Object Model (DOM) without adequate sanitization. Specifically, the issue arises because the `mermaid.render()` function's output is injected via `dangerouslySetInnerHTML`. Attackers can exploit Mermaid's per-diagram `%%{init}%%` directives to bypass security configurations, such as enabling `htmlLabels`, which permits the execution of arbitrary HTML and JavaScript for any user who views the compromised content.

Description: Docmost is open-source collaborative wiki and documentation software. In versions 0.3.0 through 0.23.2, Mermaid code block rendering is vulnerable to stored Cross-Site Scripting (XSS). The frontend can render attacker-controlled Mermaid diagrams using mermaid.render(), then inject the returned SVG/HTML into the DOM via dangerouslySetInnerHTML without sanitization. Mermaid per-diagram %%{init}%% directives allow overriding securityLevel and enabling htmlLabels, permitting arbitrary HTML/JS execution for any viewer. This issue has been fixed in version 0.24.0.
Source: security-advisories@github.com
NVD status: Analyzed
Products: docmost

Risk scores

CVSS 4.0

Type: Secondary
Base score: 6.3
Impact score: -
Exploitability score: -
Vector string: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/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
Severity: MEDIUM

CVSS 3.1

Type: Primary
Base score: 5.4
Impact score: 2.7
Exploitability score: 2.3
Vector string: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Severity: MEDIUM

Weaknesses

security-advisories@github.com: CWE-79
nvd@nist.gov: CWE-79

Hype score is a measure of social media activity compared against trending CVEs from the past 12 months. Max score 100.

Hype score: 8

Configurations

[
  {
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:docmost:docmost:*:*:*:*:*:*:*:*",
            "matchCriteriaId": "6CC11D0B-FC45-4B78-A37D-CD653CD33D2E",
            "versionEndExcluding": "0.24.0",
            "versionStartIncluding": "0.3.0",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ]
  }
]

References

Sources include official advisories and independent security research.