CVE-2026-66913: Lookyloo denial of service via zip bomb in capture imports

CVE-2026-66913 · Severity: info · CVSS 6.9 · Published 2026-07-28

Lookyloo, a tool used for analyzing web captures and website behavior, is vulnerable to a 'zip bomb' attack. An attacker can upload a specially crafted, highly compressed file that expands to an enormous size when opened, exhausting the server's memory. This can crash the service, making the analysis platform unavailable to users until it is manually restarted.

Technologies: Lookyloo. Vendors: Lookyloo.

Quick answers

Is CVE-2026-66913 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-66913 being exploited in the wild.
How severe is CVE-2026-66913?
Informational severity, with a CVSS score of 6.9, published 28 July 2026.
Which products and versions are affected?
Lookyloo <= 1.40.0.
Is there a fix for CVE-2026-66913?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-66913 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-66913?
Check whether you run Lookyloo at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A vulnerability classified as CWE-400 (Uncontrolled Resource Consumption) exists in Lookyloo due to a lack of size validation during the decompression of ZIP, gzip, and zlib archives. The application processes these files directly in memory without checking the uncompressed size, enabling 'zip bomb' attacks. An attacker can trigger this by importing a malicious capture archive or submitting compressed HAR data via the API. This results in memory exhaustion that terminates web or worker processes, leading to a persistent denial-of-service. A patch has been released that implements a 1 GB cumulative limit for archives and size-limited decompression for HAR files.

Affected products

  • Lookyloo Lookyloo <= 1.40.0

Timeline

  • 2026-07-28: disclosed
  • 2026-07-28: advisory

References

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