CVE-2026-40036

HIGH

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.

CVSS v3.1 Score

7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Published: 4/8/2026Modified: 4/17/2026

Related Intelligence (1)

HIGHVulnerability

NVD HIGH: CVE-2026-40036 — Unfurl before 2026.04 contains an unbounded zlib decompression vulnerability in ...

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.

CVE-2026-40036
NIST NVD

References (3)

https://github.com/obsidianforensics/unfurl/releases/tag/v2026.04Release Noteshttps://github.com/obsidianforensics/unfurl/security/advisories/GHSA-h5qv-qjv4-pc5mExploitVendor Advisoryhttps://www.vulncheck.com/advisories/dfir-unfurl-denial-of-service-via-unbounded-zlib-decompressionThird Party Advisory