CVE-2023-33187: highlight vulnerable to cleartext transmission of sensitive information

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-05-26 · updated 2026-06-17
Weakness: CWE-319

Description

Highlight is an open source, full-stack monitoring platform. Highlight may record passwords on customer deployments when a password html input is switched to `type="text"` via a javascript "Show Password" button. This differs from the expected behavior which always obfuscates `type="password"` inputs. A customer may assume that switching to `type="text"` would also not record this input; hence, they would not add additional `highlight-mask` css-class obfuscation to this part of the DOM, resulting in unintentional recording of a password value when a `Show Password` button is used. This issue was patched in version 6.0.0. This patch tracks changes to the `type` attribute of an input to ensure an input that used to be a `type="password"` continues to be obfuscated.

Affected products

highlight: before 6.0.0 — fixed in 6.0.0

How to fix

Upgrade to a fixed version: highlight 6.0.0. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2023-33187 or the next vulnerability affects your stack