CVE-2011-4096

CVE-2011-4096

Published Nov 17, 2011 · Updated Aug 6, 2024

The idnsGrokReply function in Squid before 3.1.16 does not properly free memory, which allows remote attackers to cause a denial of service (daemon abort) via a DNS reply containing a CNAME record that references another CNAME record that contains an empty A record.

CVSS severityUnavailable
Unscored
EPSS probability37.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

The idnsGrokReply function in Squid before 3.1.16 does not properly free memory, which allows remote attackers to cause a denial of service (daemon abort) via a DNS reply containing a CNAME record that references another CNAME record that contains an empty A record.

The record

CVE
CVE-2011-4096
Published
Nov 17, 2011
Updated
Aug 6, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Nov 17, 2011CVE 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

No CVSS assessment is available in this record.

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)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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