CVE-2026-77088

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Source
https://cve.org/CVERecord?id=CVE-2026-77088
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77088.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-77088
Aliases
Published
2026-08-23T13:34:12.574Z
Modified
2026-08-28T11:30:13.498151269Z
Severity
  • 5.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N CVSS Calculator
Summary
justhtml 0.9.0 through 1.21.0 Cross-Site Scripting via code-span
Details

justhtml versions 0.9.0 through 1.21.0 contain a cross-site scripting vulnerability in to_markdown() where inline code spans fail to account for blank lines as block boundaries. Attackers can inject blank lines into code or pre element text to break the inline span, causing sanitized HTML to be emitted unescaped and re-parsed as live Markdown by compliant renderers.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77088.json",
    "cwe_ids": [
        "CWE-79"
    ],
    "cna_assigner": "VulnCheck"
}
References

Affected packages

Git / github.com/emilstenstrom/justhtml

Affected ranges

Type
GIT
Repo
https://github.com/emilstenstrom/justhtml
Events
Introduced
e0584cb197b50a5916a7b87a29b23fe16b5261e6
Fixed
19e5c6601844b82f00f28d2b44272d89476338ee
Database specific
Show details 
{
    "source": "DESCRIPTION",
    "extracted_events": [
        {
            "introduced": "0.9.0"
        },
        {
            "fixed": "1.21.0"
        }
    ]
}

Affected versions

v0.*
v0.10.0
v0.11.0
v0.12.0
v0.13.0
v0.13.1
v0.14.0
v0.15.0
v0.16.0
v0.17.0
v0.18.0
v0.19.0
v0.20.0
v0.21.0
v0.22.0
v0.23.0
v0.24.0
v0.25.0
v0.26.0
v0.27.0
v0.28.0
v0.29.0
v0.30.0
v0.31.0
v0.32.0
v0.33.0
v0.34.0
v0.35.0
v0.36.0
v0.37.0
v0.38.0
v0.39.0
v0.40.0
v0.9.0
v1.*
v1.0.0
v1.1.0
v1.10.0
v1.11.0
v1.12.0
v1.13.0
v1.14.0
v1.15.0
v1.16.0
v1.17.0
v1.18.0
v1.19.0
v1.2.0
v1.20.0
v1.3.0
v1.4.0
v1.5.0
v1.6.0
v1.7.0
v1.8.0
v1.9.0
v1.9.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77088.json"