CVE-2021-4467 (GCVE-0-2021-4467)
Vulnerability from cvelistv5 – Published: 2025-11-14 22:51 – Updated: 2025-11-18 16:33
VLAI
EPSS
VEX
Title
Positive Technologies MaxPatrol 8 & XSpider Remote DoS
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.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-11-18 16:32 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://vulners.com/zdt/1337DAY-ID-36775 | exploit |
| https://cxsecurity.com/issue/WLB-2021090114 | exploit |
| https://www.ptsecurity.com/ | product |
| https://www.vulncheck.com/advisories/positive-tec… | third-party-advisory |
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Positive Technologies | MaxPatrol 8 (Server) |
Affected:
0 , ≤ 09.2020
(custom)
|
guessed | |
| Positive Technologies | XSpider (Server) |
Affected:
0 , ≤ 09.2020
(custom)
|
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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