Unfurl before 2026.04 contains an unbounded zlib decompression vulnerability in parse_compressed.py that allows remote attackers to cause denial of service.

Code

The project this record applies to. Exploit listings stay in References.

• Repository · github.com

Timeline

Detection, updates, and resolution for this record.

1. Apr 8, 2026 · NIST NVD

   Detected

   Unfurl before 2026.04 contains an unbounded zlib decompression vulnerability in parse_compressed.py that allows remote attackers to cause denial of service. Attackers can submit highly compressed payloads via URL parameters to the /json/visjs endpoint that expand to gigabytes, exhausting server memory and crashing the service.

2. Oct 8, 2026 · NIST NVD

   Updated

   Unfurl before 2026.04 contains an unbounded zlib decompression vulnerability in parse_compressed.py that allows remote attackers to cause denial of service. Attackers can submit highly compressed payloads via URL parameters to the /json/visjs endpoint that expand to gigabytes, exhausting server memory and crashing the service.

Affected

• cpe ryandfir/unfurlversion unspecified

Sources

• CVE.orgVulnerability recordCVE-2026-40036

  Official CVE identifier

  cve.org
• NIST NVDVulnerability recordCVE-2026-40036

  Unfurl before 2026.04 contains an unbounded zlib decompression vulnerability in parse_compressed.py that allows remote attackers to cause denial of service. Attackers can submit highly compressed payloads via URL parameters to the /json/visjs endpoint that expand to gigabytes, ex

  nvd.nist.gov

References

• Release Notes · github.com
• Exploit · github.com
• Third Party Advisory · vulncheck.com