CVE-2026-118517: CVE-2026-118517: HtmlSanitizer allowLinkHosts() / allowMediaHosts() Bypass via URLs Without a Well-Formed Authority: Incomplete Fix for CVE-2026-45066

unknown Affects symfony/html-sanitizer, symfony/symfony. Feed 2026.11.08.2, updated 2026-11-08; CVE published 2026.

CVE-2026-118517: HtmlSanitizer allowLinkHosts() / allowMediaHosts() Bypass via URLs Without a Well-Formed Authority: Incomplete Fix for CVE-2026-45066

Package
symfony/html-sanitizer Composer
Affected versions
>=6.1.0 and <6.2.0 or >=6.2.0 and <6.3.0 or >=6.3.0 and <6.4.0 or >=6.4.0 and <6.4.50 or >=7.0.0 and <7.1.0 or >=7.1.0 and <7.2.0 or >=7.2.0 and <7.3.0 or >=7.3.0 and <7.4.0 or >=7.4.0 and <7.4.23 or >=8.0.0 and <8.1.0 or >=8.1.0 and <8.1.11
Fixed in
6.4.50, 7.4.23, 8.1.11
Severity
unknown
Exploitation
not on CISA KEV · EPSS 0% (18.1th percentile)
Source
friendsofphp

References

CVE-2026-118517: HtmlSanitizer allowLinkHosts() / allowMediaHosts() Bypass via URLs Without a Well-Formed Authority: Incomplete Fix for CVE-2026-45066

Package
symfony/symfony Composer
Affected versions
>=6.1.0 and <6.2.0 or >=6.2.0 and <6.3.0 or >=6.3.0 and <6.4.0 or >=6.4.0 and <6.4.50 or >=7.0.0 and <7.1.0 or >=7.1.0 and <7.2.0 or >=7.2.0 and <7.3.0 or >=7.3.0 and <7.4.0 or >=7.4.0 and <7.4.23 or >=8.0.0 and <8.1.0 or >=8.1.0 and <8.1.11
Fixed in
6.4.50, 7.4.23, 8.1.11
Severity
unknown
Exploitation
not on CISA KEV · EPSS 0% (18.1th percentile)
Source
friendsofphp

References

NVD recordsymfony/html-sanitizer advisoriessymfony/symfony advisories

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