High 7.5Published Apr 8, 2026

CVE-2026-40036Unfurl < 2026.04 - Denial of Service via Unbounded zlib Decompression

Updated under an hour ago (2026-10-19 07:20 UTC)

Does this affect you?

It affects obsidianforensics unfurl and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for obsidianforensics unfurl

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-770, CWE-409
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Analyzed
Record last updated: Oct 8, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

obsidianforensics unfurl obsidianforensics:unfurl (from the name)	before 2026.04	CNA record
ryandfir unfurl ryandfir:unfurl	before 2026.04	NVD

References

https://github.com/obsidianforensics/unfurl/security/advisories/GHSA-h5qv-qjv4-pc5mvendor-advisory
https://github.com/obsidianforensics/unfurl/releases/tag/v2026.04release-notes, patch
https://www.vulncheck.com/advisories/dfir-unfurl-denial-of-service-via-unbounded-zlib-decompressionthird-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.