Vulnerability-Lookup

GHSA-R56F-C7P9-H5JG

Vulnerability from github – Published: 2025-08-20 18:30 – Updated: 2025-08-20 18:30

Details

Kaillera Server version 0.86 is vulnerable to a denial-of-service condition triggered by sending a malformed UDP packet after the initial handshake. Once a client sends a valid HELLO0.83 packet and receives a response, any subsequent malformed packet causes the server to crash and become unresponsive. This flaw stems from improper input validation in the server’s UDP packet handler, allowing unauthenticated remote attackers to disrupt service availability.

Severity

8.7 (High)


                  
                    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

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{
  "affected": [],
  "aliases": [
    "CVE-2011-10020"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-08-20T16:15:34Z",
    "severity": "HIGH"
  },
  "details": "Kaillera Server version 0.86 is vulnerable to a denial-of-service condition triggered by sending a malformed UDP packet after the initial handshake. Once a client sends a valid HELLO0.83 packet and receives a response, any subsequent malformed packet causes the server to crash and become unresponsive. This flaw stems from improper input validation in the server\u2019s UDP packet handler, allowing unauthenticated remote attackers to disrupt service availability.",
  "id": "GHSA-r56f-c7p9-h5jg",
  "modified": "2025-08-20T18:30:21Z",
  "published": "2025-08-20T18:30:21Z",
  "references": [
    {
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2011-10020"
    },
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      "type": "WEB",
      "url": "https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/auxiliary/dos/windows/games/kaillera.rb"
    },
    {
      "type": "WEB",
      "url": "https://www.exploit-db.com/exploits/17460"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/kaillera-server-dos-via-malformed-udp-packet"
    },
    {
      "type": "WEB",
      "url": "http://kaillera.com"
    }
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  "schema_version": "1.4.0",
  "severity": [
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      "score": "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",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2011-10020 (GCVE-0-2011-10020)

Vulnerability from cvelistv5 – Published: 2025-08-20 15:35 – Updated: 2026-05-15 11:13 Unsupported When Assigned

Title

Kaillera 0.86 Server DoS via Malformed UDP Packet

Summary

Severity

8.7 (High)


                        
                          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

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-08-22 16:21 UTC

CWE

CWE-20 - Improper Input Validation

Assigner

VulnCheck CNA under the mitre root

CNA scorecard B 84/100 over 6929 records in the last 180 days details

References

4 references

URL	Tags
https://raw.githubusercontent.com/rapid7/metasplo…	exploit
https://www.exploit-db.com/exploits/17460	exploit
http://kaillera.com/	product
https://www.vulncheck.com/advisories/kaillera-ser…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
Kaillera Project	Server	Affected: 0 , ≤ 0.86 (custom)

Date Public

2011-06-30 00:00

Credits

Sil3nt_Dre4m

Show details on NVD website

JSON

To clipboard

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                "timestamp": "2025-08-22T16:21:09.395156Z",
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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.

Vulnerability timeline

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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.
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