CVE Explorer
CVE-2026-30838
league/commonmark is a PHP Markdown parser. Prior to version 2.8.1, the DisallowedRawHtml extension can be bypassed by inserting a newline, tab, or other ASCII whitespace character between a disallowed HTML tag name and the closing >. For example, <script\n> would pass through unfiltered and be rendered as a valid HTML tag by browsers. This is a cross-site scripting (XSS) vector for any application that relies on this extension to sanitize untrusted user input. All applications using the Disallo
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
0
Affected products and versions
1 source assertion{"product":"commonmark","vendor":"thephpleague","versions":[{"status":"affected","version":"< 2.8.1"}]}
- cve_program_cvelist_v5affectedurn:baitaphish:normalized-source-record:v2:941d75d8fe5d7dfa8853ad2b18f09ac95a77776ab6a27cc9dcf1c0b3ddd36a33 · sha256:68997381e95ed440… · /containers/cna/affected/0
Provider-owned CVSS observations
1 source assertion{"metric":{"attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"NETWORK","baseScore":5.1,"baseSeverity":"MEDIUM","privilegesRequired":"LOW","subAvailabilityImpact":"NONE","subConfidentialityImpact":"LOW","subIntegrityImpact":"LOW","userInteraction":"PASSIVE","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW"},"metric_type":"cvssV4_0"}
- cve_program_cvelist_v5cvssurn:baitaphish:normalized-source-record:v2:941d75d8fe5d7dfa8853ad2b18f09ac95a77776ab6a27cc9dcf1c0b3ddd36a33 · sha256:68997381e95ed440… · /containers/cna/metrics/0/cvssV4_0
CWE assertions
1 source assertion{"cweId":"CWE-79","description":"CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')","lang":"en","type":"CWE"}
- cve_program_cvelist_v5cweurn:baitaphish:normalized-source-record:v2:941d75d8fe5d7dfa8853ad2b18f09ac95a77776ab6a27cc9dcf1c0b3ddd36a33 · sha256:68997381e95ed440… · /containers/cna/problemTypes/0/descriptions/0
Source references
1 source assertion{"name":"https://github.com/thephpleague/commonmark/security/advisories/GHSA-4v6x-c7xx-hw9f","tags":["x_refsource_CONFIRM"],"url":"https://github.com/thephpleague/commonmark/security/advisories/GHSA-4v6x-c7xx-hw9f"}
- cve_program_cvelist_v5referenceurn:baitaphish:normalized-source-record:v2:941d75d8fe5d7dfa8853ad2b18f09ac95a77776ab6a27cc9dcf1c0b3ddd36a33 · sha256:68997381e95ed440… · /containers/cna/references/0
Attribution and limitations
- CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →
Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.