Medium · CVSS 6.9CVE-2026-55835

Lookyloo: Potential sub-system DoS due to parameter missmatch in notificationCVE-2026-55835

Answer in brief

CVE-2026-55835 records a Medium severity (CVSS 6.9) vulnerability in Lookyloo: Potential sub-system DoS due to parameter missmatch in notification. The current sources do not mark it as known exploited. The current feed maps Lookyloo/lookyloo (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 23, 2026Updated Oct 23, 2026Source checked Oct 23, 2026First seen by HOL Oct 23, 2026Material review Oct 23, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.9
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 6.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Lookyloo/lookyloo (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Lookyloo/lookyloogeneric	<1.39.4	1.39.4

Recommended response

Check inventory. Check lockfiles and deployed manifests for Lookyloo/lookyloo.
Review the reported fix. Update Lookyloo/lookyloo to 1.39.4 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 23, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 23, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 23, 2026

Sources and claim methodology

Upstream source description

Lookyloo is a web interface that allows users to capture a website page and then display a tree of domains that call each other. Prior to version 1.39.4, an unauthenticated user can trigger Lookyloo's "report a capture" email on demand (this is expected). The /json/<uuid>/report API endpoint (CaptureReport) is incorrectly passing the email and comment parameters, overwriting as_admin. When True, as_admin will trigger a search query on a MISP instance (if configured) and add a list of matching URLs in the email sent to the analyst (not the submitter, so there is no risk of leaking information) . It could potentially cause a DoS on the MISP instance. This issue has been patched in version 1.39.4.

Quoted source text, attributed separately from HOL analysis.