VulnerabilityModified

CVE-2016-9909

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.

MEDIUM 6.1EPSS 2.16%

Does this matter?

Lower severity and a low EPSS score (2.16%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.0: 6.1 MEDIUMCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS: 2.16% probability · 81th percentile
CISA KEV: Not listed
Weakness: CWE-79
Affected: html5lib/html5lib
Source: secalert@redhat.com

References

http://www.openwall.com/lists/oss-security/2016/12/06/5Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/12/08/8Mailing List, Patch, Third Party Advisory
http://www.securityfocus.com/bid/95132Third Party Advisory, VDB Entry
https://github.com/html5lib/html5lib-python/commit/9b8d8eb5afbc066b7fac9390f5ec75e5e8a7cab7Patch
https://github.com/html5lib/html5lib-python/issues/11Vendor Advisory
https://github.com/html5lib/html5lib-python/issues/12Vendor Advisory
https://html5lib.readthedocs.io/en/latest/changes.html#b9Release Notes
http://www.openwall.com/lists/oss-security/2016/12/06/5Mailing List, Patch, Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/12/08/8Mailing List, Patch, Third Party Advisory
http://www.securityfocus.com/bid/95132Third Party Advisory, VDB Entry
https://github.com/html5lib/html5lib-python/commit/9b8d8eb5afbc066b7fac9390f5ec75e5e8a7cab7Patch
https://github.com/html5lib/html5lib-python/issues/11Vendor Advisory
https://github.com/html5lib/html5lib-python/issues/12Vendor Advisory
https://html5lib.readthedocs.io/en/latest/changes.html#b9Release Notes

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.