CVE-2012-4434Network attack vector

Authenticated DoS or code execution via buffer overflow

Published Jan 9, 2020 · Updated Aug 6, 2024

Buffer overflow in fwknop before 2.0.3 allows remote authenticated users to crash the server or execute arbitrary code via crafted SPA requests. In fwknopd server/access.c, fixed-size stack buffers receive attacker-controlled protocol and port strings without adequate length checks while parsing an authenticated request. Exploitation requires a valid authenticated SPA request; consequences range from daemon crash to possible code execution.

CVSS severity8.8
High
EPSS probability3.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in fwknop before 2.0.3 allows remote authenticated users to crash the server or execute arbitrary code via crafted SPA requests. In fwknopd server/access.c, fixed-size stack buffers receive attacker-controlled protocol and port strings without adequate length checks while parsing an authenticated request. Exploitation requires a valid authenticated SPA request; consequences range from daemon crash to possible code execution.

The record

CVE
CVE-2012-4434
Published
Jan 9, 2020
Updated
Aug 6, 2024
Vendor
fwknop
Product
fwknop
Classifications
CWE-119, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 9, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 6, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=before 2.0.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

fwknop · fwknopversion=before 2.0.3

Published CVSS scores

6.5NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
8.8NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-119Buffer Overflow
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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