CVE-2020-4070
In CSS Validator less than or equal to commit 54d68a1, there is a cross-site scripting vulnerability in handling URIs.
Does this matter?
Lower severity and a low EPSS score (0.55%). Track it; it rarely justifies an emergency change on its own.
Description
In CSS Validator less than or equal to commit 54d68a1, there is a cross-site scripting vulnerability in handling URIs. A user would have to click on a specifically crafted validator link to trigger it. This has been patched in commit e5c09a9.
- CVSS 3.1
- 5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 0.55% probability · 46th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- w3c/css validator
- Source
- security-advisories@github.com
EPSS 0.5% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/w3c/css-validator/commit/e5c09a9119167d3064db786d5f00d730b584a53bPatch
- https://github.com/w3c/css-validator/security/advisories/GHSA-wf36-7w73-rh8cVendor Advisory
- https://github.com/w3c/css-validator/commit/e5c09a9119167d3064db786d5f00d730b584a53bPatch
- https://github.com/w3c/css-validator/security/advisories/GHSA-wf36-7w73-rh8cVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.