HOMEVULNERABILITIESCVE-2020-27783
MEDIUM

CVE-2020-27783

CWE-79Published: December 3, 2020· Updated: Jun 17, 2026

6.1
CVSS v3.1

Official Description

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.

NVD Source

Technical Analysis

CVE-2020-27783 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeChanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected Vendors & Products

Debian1 product(s)
debian linux
Fedora1 product(s)
fedora
lxml1 product(s)
lxml
netapp1 product(s)
snapcenter
Oracle2 product(s)
communications offline mediation controllerzfs storage appliance kit
Red Hat2 product(s)
software collectionsenterprise linux
Source: NVD CPE · 10 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (16)

https://bugzilla.redhat.com/show_bug.cgi?id=1901633Exploit · Issue Tracking · Patch · Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1901633Exploit · Issue Tracking · Patch · Third Party Advisory

Quick Facts

CVE IDCVE-2020-27783
CVSS Score6.1 / 10
SeverityMEDIUM
WeaknessCWE-79
CISA KEVNo
Affected6 vendor(s)
PublishedDec 3, 2020

Related CVEs (CWE-79)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2020-27783 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.