CVE-2021-4467 json
Positive Technologies MaxPatrol 8 & XSpider Remote DoS
published 2025-11-14 11 mo ago modified 2026-06-17 4 mo ago also EUVD-2021-34719
- cvss
- 8.7
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 11 mo ago
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- vulners.com https://vulners.com/zdt/1337DAY-ID-36775 referenced PoC, tagged "exploit" by a source, unverified
- cxsecurity.com https://cxsecurity.com/issue/WLB-2021090114 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | 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 |
| CNA | 4.0 | 8.7 | 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:X/V:X/RE:X/U:X |
Affected products
- Positive Technologies MaxPatrol 8 (Server)
- Positive Technologies XSpider (Server)
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
vulners.com
/zdt/1337DAY-ID-36775
exploit
-
cxsecurity.com
/issue/WLB-2021090114
exploit
-
ptsecurity.com
/
product
-
vulncheck.com
/advisories/positive-technologies-maxpatrol-8-and-xspider-remote-dos
third-party-advisory
Sources
- CVE List CVE-2021-4467
- NVD CVE-2021-4467
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