High severity · published Oct 17, 2026
CVE-2026-111924
Fleet before 4.83.0 Denial of Service via Unbounded Gzip Decompression
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
Fleet before 4.83.0 contains a denial of service vulnerability that allows unauthenticated attackers to exhaust server memory by sending gzip-compressed request bodies. Attackers can send small, highly compressed requests with Content-Encoding: gzip to unauthenticated endpoints that expand during decoding, crashing the entire Fleet instance.
CVSS vector
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
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 30% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FL
fleet · fleetdm
before 4.83.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-111924
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-111924
github.com
https://github.com/fleetdm/fleet/security/advisories/GHSA-3982-g48v-9rwh
www.vulncheck.com
https://www.vulncheck.com/advisories/fleet-before-4.83.0-denial-of-service-via-unbounded-gzip-decompression
More from fleet
9.8
CVE-2026-26191
Fleet vulnerable to OS command injection in software packages
9.8
CVE-2026-34387
Fleet vulnerable to OS command injection via crafted software package metadata in uninstall scripts
9.8
CVE-2026-23518
Fleet has a JWT signature bypass vulnerability in Azure AD MDM enrollment
9.8
CVE-2020-26276
Fleet is an open source osquery manager
9.3
CVE-2025-27509
SAML authentication vulnerability due to improper SAML response validation