How severe is CVE-2020-8450?

CVE-2020-8450 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2020-8450 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 72% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8450?

CVE-2020-8450 primarily affects Squid-cache Squid. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-8450?

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-2020-8450 published?

CVE-2020-8450 was published on 2020-02-04 and last updated on 2026-06-17.

CVE-2020-8450

CVE-2020-8450 is a high-severity vulnerability in Squid-cache Squid with a CVSS 3.x base score of 7.3. Its EPSS exploit-prediction score of 72% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-131.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 7.5
EPSS exploit prediction: 72% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-131
Affected product: Squid-cache Squid
Published: 2020-02-04
Last modified: 2026-06-17

Description

An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.

Frequently asked questions

What is CVE-2020-8450?: An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.
How severe is CVE-2020-8450?: CVE-2020-8450 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2020-8450 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 72% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8450?: CVE-2020-8450 primarily affects Squid-cache Squid. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-8450?: 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-2020-8450 published?: CVE-2020-8450 was published on 2020-02-04 and last updated on 2026-06-17.

References

Affected products (9)

cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:19.10:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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CVE-2026-20911 — Critical (CVSS 9.8): A heap-based buffer overflow vulnerability exists in the HuffTable::initval functionality of LibRaw Commit 0b56545 and…
CVE-2025-1861 — Critical (CVSS 9.8): In PHP from 8.1.* before 8.1.32, from 8.2.* before 8.2.28, from 8.3.* before 8.3.19, from 8.4.* before 8.4.5, when…
CVE-2023-5941 — Critical (CVSS 9.8): In versions of FreeBSD 12.4-RELEASE prior to 12.4-RELEASE-p7 and FreeBSD 13.2-RELEASE prior to 13.2-RELEASE-p5 the…

Browse all CWE-131 (Incorrect Calculation of Buffer Size) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

200.89.159.59 (ipv4-addr)
192.3.127.40 (ipv4-addr)