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CVE-2016-9909
The serializer in html5lib before 0.99999999 might allow remote attackers to conduct cross-site scripting (XSS) attacks by leveraging…
Medium6.1EPSS 2.2%
- Published
- Updated
- Reserved
- Assigned by
- redhat
Description
The serializer in html5lib before 0.99999999 might allow remote attackers to conduct cross-site scripting (XSS) attacks by leveraging mishandling of the < (less than) character in attribute values.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | Medium6.1 | CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 2.2% · top 18% of all CVEs (2 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.1.
Weakness
Affected products
n/a
- affected n/a
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIhtml5libGHSA-v9v9-xffq-rwr4 (opens in a new tab)
References (7)
- https://github.com/html5lib/html5lib-python/issues/12 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://html5lib.readthedocs.io/en/latest/changes.html#b9 (opens in a new tab)x_refsource_CONFIRMx_transferred
- [oss-security] 20161206 CVE Request: html5lib: potential cross-site scripting vulnerablity: quote attributes that need escaping in legacy browsers (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- [oss-security] 20161208 Re: CVE Request: html5lib: potential cross-site scripting vulnerablity: quote attributes that need escaping in legacy browsers (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- 95132 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- https://github.com/html5lib/html5lib-python/commit/9b8d8eb5afbc066b7fac9390f5ec75e5e8a7cab7 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/html5lib/html5lib-python/issues/11 (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-v9v9-xffq-rwr4 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Record last updated .