Which products and versions are affected by CVE-2011-4040?

Affected: Njstar Communicator versions 3.0.11818. The full list is in the CVE brief.

Is CVE-2011-4040 being exploited in the wild?

It is not listed in any known-exploited vulnerabilities catalog.

Is CVE-2011-4040 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2011-4040?

Public exploit code is available.

Is there a fix for CVE-2011-4040?

No fixed version is listed yet; check the vendor advisory for mitigations.

How urgently should CVE-2011-4040 be patched?

Brandefense priority: patch immediately, because it is very likely to be exploited soon.

Request A Demo

Vulnerability Intelligence

CVE-2011-4040

CriticalPublic exploit

Buffer overflow in MiniSmtp 3.0.11818 in NJStar Communicator allows remote attackers to execute arbitrary code via a crafted packet.

Published Nov 21, 2011 · Updated Apr 28, 2026

Key Facts

Patch immediately

CVE-2011-4040 is a critical-severity vulnerability (CVSS 10.0 v2) affecting Njstar Communicator.
It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
EPSS estimates a 65% probability of exploitation in the next 30 days.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

CVSS v2

10.0

AV:N/AC:L/Au:N/C:C/I:C/A:C

EPSS (30-day exploit likelihood)

65%

Higher than 99.2% of all scored CVEs

Exploited in the wild

No known

Not in a known-exploited catalog

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2011-4040 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

Buffer overflow in MiniSmtp 3.0.11818 in NJStar Communicator allows remote attackers to execute arbitrary code via a crafted packet.

Affected Products

1 affected entries in total

Product	Affected versions	Fixed in
Njstar CommunicatorNjstar	3.0.11818	n/a

Timeline

Publicly disclosed
Nov 21, 2011
Last updated
Apr 28, 2026

Weakness Type

CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

FAQ

Common Questions.

Buffer overflow in MiniSmtp 3.0.11818 in NJStar Communicator allows remote attackers to execute arbitrary code via a crafted packet.
Affected: Njstar Communicator versions 3.0.11818. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

Is CVE-2011-4040 Running On Your Attack Surface?

Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.