How severe is CVE-2016-2572?

CVE-2016-2572 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2016-2572 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-2572?

CVE-2016-2572 primarily affects Squid-cache Squid. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-2572?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2016-2572 published?

CVE-2016-2572 was published on 2016-02-27 and last updated on 2026-06-17.

CVE-2016-2572

CVE-2016-2572 is a high-severity vulnerability in Squid-cache Squid with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 10% places it in the 95th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Squid-cache Squid
Published: 2016-02-27
Last modified: 2026-06-17

Description

http.cc in Squid 4.x before 4.0.7 relies on the HTTP status code after a response-parsing failure, which allows remote HTTP servers to cause a denial of service (assertion failure and daemon exit) via a malformed response.

Frequently asked questions

What is CVE-2016-2572?: http.cc in Squid 4.x before 4.0.7 relies on the HTTP status code after a response-parsing failure, which allows remote HTTP servers to cause a denial of service (assertion failure and daemon exit) via a malformed response.
How severe is CVE-2016-2572?: CVE-2016-2572 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2016-2572 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-2572?: CVE-2016-2572 primarily affects Squid-cache Squid. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-2572?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2016-2572 published?: CVE-2016-2572 was published on 2016-02-27 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:squid-cache:squid:4.0.1:*:*:*:*:*:*:*
cpe:2.3:a:squid-cache:squid:4.0.2:*:*:*:*:*:*:*
cpe:2.3:a:squid-cache:squid:4.0.3:*:*:*:*:*:*:*
cpe:2.3:a:squid-cache:squid:4.0.4:*:*:*:*:*:*:*
cpe:2.3:a:squid-cache:squid:4.0.5:*:*:*:*:*:*:*
cpe:2.3:a:squid-cache:squid:4.0.6:*:*:*:*:*:*:*

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