Read the docs

Unbounded gzip decompression in Fleet enables denial of service

Priority MEDIUM 44CWE-409Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Fleet before 4.83.0 contains a denial of service flaw in how it handles gzip-compressed request bodies. A missing limit on decompressed size lets an unauthenticated remote attacker send small, highly compressed requests that expand in memory during decoding, exhausting server memory and crashing the Fleet instance. The flaw is tracked under CWE-409.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00359 29th percentileScored 2026-11-07
Fix Fixed fleet (fleetdm): 4.83.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
fleetdmfleetbefore 4.83.04.83.0Patch availableCNA
  • fleet Vendorfleetdm Affected before 4.83.0 Fixed in 4.83.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:*——fleetdm
  • cpe:2.3:a:fleetdm:fleet:*:*:*:*:*:*:*:* Versions — — ·fleetdm

Remediation

Upgrade Fleet to version 4.83.0 or later.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA fleet (fleetdm) Fixed in 4.83.0

Timeline

  1. 2026-10-18 Threatist record created from CVE-2026-111924
  2. 2026-10-18 Alias added: GHSA-7fp2-q7fp-2qwf
  3. 2026-10-18 Priority changed: MEDIUM → LOW
  4. 2026-10-20 CISA SSVC decision points changed
  5. 2026-10-20 Priority changed: LOW → MEDIUM

References

  • TI-2026-29868 Fleet: Cross-Team Policy Data Exposure via Global Policy Read Endpoint CVSS 3.1MEDIUM 4.3
  • TI-2025-20341 SAML authentication vulnerability due to improper SAML response validation CVSS 4.0CRITICAL 9.3
  • TI-2026-65639 Fleet before 4.87.0 Authentication Bypass via Device Identifiers CVSS 4.0CRITICAL 9.3
  • TI-2026-18942 Fleet has a JWT signature bypass vulnerability in Azure AD MDM enrollment CVSS 4.0CRITICAL 9.3
  • TI-2020-16097 SAML authentication vulnerability in Fleet CVSS 3.1CRITICAL 10.0
  • TI-2026-76129 Unbounded recursion in Fleet Apple MDM enrollment lets attackers crash server CVSS 4.0HIGH 8.7
See all 40 →

Sources