CRITICALVulnerability

CVE-2026-66421

OpenClaw Dashboard contains a stored cross-site scripting vulnerability that allows unauthenticated remote attackers to execute arbitrary JavaScript in the administrator's browser session by injecting HTML markup into agent transcript messages processed through the sessions API. Attackers can craft a message containing inline event handler payloads such as an img tag with an onerror attribute within the 60-character rendering budget, which is stored in the session transcript and interpolated unsanitized into innerHTML on the default landing page, allowing theft of session tokens and unauthorized calls to authenticated administrative endpoints including agent instruction file modification.

Properties

severity
CRITICAL
score
9.3
cve_id
CVE-2026-66421
vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
published_at
2026-07-30T23:16:53.687
last_modified
2026-08-31T20:25:28.573

Related Entities (2)

HAS_WEAKNESS (1)

[Weakness]Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

DESCRIBED_BY (1)

[Source]NVD

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CVE-2026-66421 — Ninja Signal Threat Intelligence | Ninja Signal