VDB
ALPINE-CVE-2021-28957
ALPINE-CVE-2021-28957
PUBLISHED
CVSS 6.099999904632568 MEDIUM
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 sanitizer. A remote attacker could exploit this flaw to run arbitrary JS code on users who interact with incorrectly sanitized HTML. This issue is patched in lxml 4.6.3.
Risk Scores
CVSS v3.1
6.099999904632568
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Alpine:v3.16 | py3-lxml | 4.6.2-r0, 4.6.1-r0, 4.6.0-r0 |
| Alpine:v3.20 | py3-lxml | 4.6.2-r0, 0, 2.2.6-r0 |
| Alpine:v3.21 | py3-lxml | 4.6.2-r0, 4.6.1-r0, 4.6.0-r0 |
| Alpine:v3.19 | py3-lxml | 2.2.6-r0, 0, 2.2.8-r0 |
| Alpine:v3.18 | py3-lxml | 4.6.2-r0, 4.6.1-r0, 4.6.0-r0 |
| Alpine:v3.22 | py3-lxml | 4.6.2-r0, 4.6.1-r0, 4.6.0-r0 |
| Alpine:v3.17 | py3-lxml | 0, 2.2.6-r0, 2.2.8-r0 |
| Alpine:v3.23 | py3-lxml | 0, 2.2.6-r0, 2.2.8-r0 |
Timeline
- Mar 21, 2021 CVE Published
- Dec 3, 2025 CVE Updated
- Apr 30, 2026 Distribution Patch