DNS: Squid DNS Replies Invalid Free

This signature detects attempts to exploit a known vulnerability against Squid while processing certain DNS replies. A successful attack can lead to arbitrary code execution.

Extended Description

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.

Affected Products

Squid-cache squid

References

BugTraq: 50449

CVE: CVE-2011-4096

Short Name
DNS:SQUID-DNS-REPLIES2
Severity
Minor
Recommended
False
Recommended Action
Drop
Category
DNS
Keywords
CVE-2011-4096 DNS Free Invalid Replies Squid bid:50449
Release Date
03/23/2017
Supported Platforms

srx-branch-12.3

srx-19.3

srx-branch-19.3

vsrx3bsd-19.2

srx-branch-19.4

vsrx-19.4

mx-12.3

mx-19.4

vmx-19.4

mx-19.3

vsrx3bsd-19.4

srx-19.4

vsrx-12.3

vmx-19.3

vsrx-19.2

srx-12.3

Sigpack Version
3761
False Positive
Unknown
Vendors

Squid-cache

CVSS Score

5.0

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