XSS in Lxml
CVE-2021-28957
An XSS vulnerability was discovered in python-lxml's clean module versions before 4.6.3. When disabling the safe_attrs_only and forms arguments, the Cleaner class does not remove the formaction attribute allowing for JS to bypass the sanit…
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.040 (89.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
Affected products
- Lxml
- Netapp Snapcenter
- Oracle Zfs_storage_appliance_kit — versions 8.8
- Debian Debian_linux — versions 9.0, 10.0
- Fedoraproject Fedora — versions 33, 34
- N/a — versions n/a
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (Exploit, Third Party Advisory, x_refsource_MISC, Issue Tracking)
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
- cve@mitre.org (x_refsource_FEDORA, vendor-advisory)
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (x_refsource_CONFIRM, Third Party Advisory)
- cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
Frequently asked questions
- What is CVE-2021-28957?
- CVE-2021-28957 is a medium-severity vulnerability in Lxml, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-03-21.
- How severe is CVE-2021-28957?
- Medium severity. CVSS v3 base score is 6.1 out of 10.
- Is CVE-2021-28957 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.