CVE-2026-44253

Wazuh: Cluster Protocol Memory Exhaustion (DoS) via unbounded receive_str allocation and div_msg_box accumulation

MEDIUM
4.9
CVSS Score
Published: August 19, 2026 at 04:06 PM UTC
Updated: October 27, 2026 at 11:10 AM UTC
1 product affected across 1 vendorWazuh

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Severity
MEDIUM4.9
Exploit prediction
EPSS 0.6%
SSVC
PoC

Description

Wazuh is a free and open source platform used for threat prevention, detection, and response. From 3.9.0 until 4.14.5 and 5.0.0-beta2, the Wazuh cluster protocol in framework/wazuh/core/cluster/common.py allows an authenticated cluster node to exhaust memory on the master. The receive_str() method accepts an attacker-controlled total for InBuffer without a maximum, so a new_str command can request a multi-gigabyte bytearray and repeated requests accumulate in in_str. The divided-message path also retains flag_divided fragments under unique counters in div_msg_box without a count, aggregate-size, or expiration limit. Exploitation can disrupt agent connectivity and alert processing across the monitored environment. This issue is fixed in versions 4.14.5 and 5.0.0-beta2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.9.0 ≤ v < 4.14.55.0.05.0.0 beta1
Affected range stops below 4.14.5, so it looks safe — our inference, not a vendor statement
Affected range stops below 5.0.0-beta2, so it looks safe — our inference, not a vendor statement

References (4)

x_refsource_CONFIRMExploitVendor Advisory
Source: cverecord
https://github.com/wazuh/wazuh/security/advisories/GHSA-h5r8-gvhv-cmp2
x_refsource_MISCIssue TrackingPatch
Source: cverecord
https://github.com/wazuh/wazuh/pull/35173
x_refsource_MISCPatchRelease Notes
Source: cverecord
https://github.com/wazuh/wazuh/releases/tag/v4.14.5

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.9MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-789CWE-770

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