CVE-2013-4123

CVE-2013-4123 is a medium-severity vulnerability in Squid-cache Squid with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 80% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Description

client_side_request.cc in Squid 3.2.x before 3.2.13 and 3.3.x before 3.3.8 allows remote attackers to cause a denial of service via a crafted port number in a HTTP Host header.

Frequently asked questions

What is CVE-2013-4123?
client_side_request.cc in Squid 3.2.x before 3.2.13 and 3.3.x before 3.3.8 allows remote attackers to cause a denial of service via a crafted port number in a HTTP Host header.
How severe is CVE-2013-4123?
CVE-2013-4123 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2013-4123 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 80% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-4123?
CVE-2013-4123 primarily affects Squid-cache Squid. In total, 42 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-4123?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2013-4123 published?
CVE-2013-4123 was published on 2013-09-16 and last updated on 2026-06-16.

References

Affected products (42)

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