01 Record
CVE-2026-66370
html_sanitize_ex HTML5 scrubber keeps attacker-supplied form-association attributes, allowing form hijacking
MediumPUBLISHEDCNA: EEF
CNA base score4.8 CVSS v4.0CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N
02 Description
html_sanitize_ex HTML5 scrubber keeps attacker-supplied form-association attributes, allowing form hijacking
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.40% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 34.2% of scored records. A rank, not a probability.
- NVD base score
- 4.8 (CVSS v4.0), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- NVD analysis status
- Modified. NVD last modified this record on 2026-10-24.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-08-06 14:49Z2 MO AGO
- Last updated
- 2026-08-19 11:51Z2 MO AGO
- Reserved
- 2026-08-06
- Assigning CNA
- EEF
- Record state
- PUBLISHED
- Severity
- Medium (CVSS 4.8)
- CNA CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N
- Weaknesses
- CWE-601URL Redirection to Untrusted Site ('Open Redirect')Base
- Data version
- 5.2
- Document digest
- 572b67ebbee4c9cd079d0a2f3fc591eb790b56b58dc28ff298cd43f5e426d7f1
05 Affected products
VendorProductVersionsPlatforms
rrrenehtml_sanitize_ex0.3.1 to < 1.4.5, 1.5.0-rc.0 to < 1.5.3, 8976d64ea0b77d26093a94a43ec48a3978e8d028 to < *—
06 References
- github.comhttps://github.com/rrrene/html_sanitize_ex/security/advisories/GHSA-w3f9-jjhw-wwvq
- cna.erlef.orghttps://cna.erlef.org/cves/CVE-2026-66370.html
- osv.devhttps://osv.dev/vulnerability/EEF-CVE-2026-66370
- github.comhttps://github.com/rrrene/html_sanitize_ex/commit/a1e804ed997e780ea71d14393cf2f701330553a6
- github.comhttps://github.com/rrrene/html_sanitize_ex/commit/21394e758cb0ffe12fb9953c30fdedc6016c8f9e