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Vulnerability record · CVE-2021-4467 · published 14 November 2025

CVE-2021-4467: Uncontrolled resource consumption vulnerability

Positive Technologies MaxPatrol 8 and XSpider contain a remote denial-of-service vulnerability in the client communication service on TCP port 2002. The service generates a new session identifier for each incoming connection without adequately limiting concurrent requests. An unauthenticated remote attacker can repeatedly issue HTTPS requests to the service, causing excessive allocation of session identifiers. Under load, session identifier collisions may occur, forcing active client sessions to disconnect and resulting in service disruption.

8.7 CVSS 4.0 High EPSS 0.46% · top 62.6% CWE-400 · Uncontrolled resource consumption Deferred
8.7CVSS 4.0 base score
0.46%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
6References
17 Jun 2026Last modified by NVD

Description

Positive Technologies MaxPatrol 8 and XSpider contain a remote denial-of-service vulnerability in the client communication service on TCP port 2002. The service generates a new session identifier for each incoming connection without adequately limiting concurrent requests. An unauthenticated remote attacker can repeatedly issue HTTPS requests to the service, causing excessive allocation of session identifiers. Under load, session identifier collisions may occur, forcing active client sessions to disconnect and resulting in service disruption.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

References

LinkTags
https://cxsecurity.com/issue/WLB-2021090114
https://vulners.com/zdt/1337DAY-ID-36775
https://www.ptsecurity.com/
https://www.vulncheck.com/advisories/positive-technologies-maxpatrol-8-and-xspider-remote-dos
https://cxsecurity.com/issue/WLB-2021090114
https://vulners.com/zdt/1337DAY-ID-36775

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Source: NIST National Vulnerability Database (record CVE-2021-4467), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.