XSS in Lxml
CVE-2020-27783
A XSS vulnerability was discovered in python-lxml's clean module. The module's parser didn't properly imitate browsers, which caused different behaviors between the sanitizer and the user's page. A remote attacker could exploit this flaw to run arbitrary HTML/JS code.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.040 (90.4th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 90.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.040 · newest: 0.040 · change: 0.000
Affected products
- Lxml
- NetApp Snapcenter
- Oracle Communications Offline Mediation Controller — versions 12.0.0.3.0
- Oracle Zfs Storage Appliance Kit — versions 8.8
- Debian Linux — versions 9.0, 10.0
- Fedoraproject Fedora — versions 32, 33
- Red Hat Enterprise Linux — versions 8.0
- Red Hat Software Collections
- Python-Lxml — versions lxml-4.6.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.redhat.com/show_bug.cgi (Exploit, Patch, Third Party Advisory, Issue Tracking)
- www.debian.org/security/2020/dsa-4810 (vendor-advisory, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2020/12/msg00028.html (mailing-list, Mailing List, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- www.oracle.com//security-alerts/cpujul2021.html (Patch, Third Party Advisory)
- advisory.checkmarx.net/advisory/CX-2020-4286 (Exploit, Third Party Advisory)
- security.netapp.com/advisory/ntap-20210521-0003/ (Third Party Advisory)
Frequently asked questions
- What is CVE-2020-27783?
- CVE-2020-27783 is a medium-severity vulnerability in Lxml, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2020-12-03.
- How severe is CVE-2020-27783?
- Medium severity. CVSS v3 base score is 6.1 out of 10.
- Is CVE-2020-27783 known to be exploited?
- 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.