How severe is CVE-2010-2951?

CVE-2010-2951 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2010-2951 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2010-2951?

CVE-2010-2951 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2010-2951?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2010-2951 published?

CVE-2010-2951 was published on 2010-10-12 and last updated on 2026-06-16.

CVE-2010-2951

CVE-2010-2951 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 31% places it in the 98th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 31% (98th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Squid-cache Squid
Published: 2010-10-12
Last modified: 2026-06-16

Description

dns_internal.cc in Squid 3.1.6, when IPv6 DNS resolution is not enabled, accesses an invalid socket during an IPv4 TCP DNS query, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via vectors that trigger an IPv4 DNS response with the TC bit set.

Frequently asked questions

What is CVE-2010-2951?: dns_internal.cc in Squid 3.1.6, when IPv6 DNS resolution is not enabled, accesses an invalid socket during an IPv4 TCP DNS query, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via vectors that trigger an IPv4 DNS response with the TC bit set.
How severe is CVE-2010-2951?: CVE-2010-2951 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2010-2951 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2010-2951?: CVE-2010-2951 affects Squid-cache Squid. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2010-2951?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2010-2951 published?: CVE-2010-2951 was published on 2010-10-12 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:squid-cache:squid:3.1.6:*:*:*:*:*:*:*

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