ReviewHigh
CVE-2026-77115
Brave
Brave Popup Builder (brave-popup-builder) up to version 0.8.5 reflects UTM query parameters into popup form HTML without escaping them.
- CVSS
- 7.1
- EPSS
- - - percentile
- CISA KEV
- Not listed
- Published
- 2026.08.23
Review
The CVSS severity warrants an early asset and exposure review.
Known exploitationNot established by KEV
Exploit probability-
Technical severityCVSS 7.1
Vulnerability overview
Brave Popup Builder (brave-popup-builder) up to version 0.8.5 reflects UTM query parameters into popup form HTML without escaping them.
Affected product and versions
- Product
- Brave
- Affected versions
- < 0.8.6
- Fixed versions
- No verified fixed-version field is available yet
Recommended response sequence
Confirm exposure before applying a vendor-supported change.
- 1Identify
Confirm that Brave and an affected version are present.
- 2Prioritize
Combine exploitation signals with asset exposure and business criticality.
- 3Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
- 4Verify
Recheck the version, service health, access paths, and relevant logs.
Technical data
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
- CWE
- CWE-79