How severe is CVE-2021-32565?

CVE-2021-32565 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 high, and availability none.

Is CVE-2021-32565 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32565?

CVE-2021-32565 primarily affects Apache Traffic Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-32565?

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-2021-32565 published?

CVE-2021-32565 was published on 2021-06-29 and last updated on 2026-06-17.

CVE-2021-32565

CVE-2021-32565 is a high-severity vulnerability in Apache Traffic Server with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-444.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-444
Affected product: Apache Traffic Server
Published: 2021-06-29
Last modified: 2026-06-17

Description

Invalid values in the Content-Length header sent to Apache Traffic Server allows an attacker to smuggle requests. This issue affects Apache Traffic Server 7.0.0 to 7.1.12, 8.0.0 to 8.1.1, 9.0.0 to 9.0.1.

Frequently asked questions

What is CVE-2021-32565?: Invalid values in the Content-Length header sent to Apache Traffic Server allows an attacker to smuggle requests. This issue affects Apache Traffic Server 7.0.0 to 7.1.12, 8.0.0 to 8.1.1, 9.0.0 to 9.0.1.
How severe is CVE-2021-32565?: CVE-2021-32565 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 high, and availability none.
Is CVE-2021-32565 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32565?: CVE-2021-32565 primarily affects Apache Traffic Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-32565?: 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-2021-32565 published?: CVE-2021-32565 was published on 2021-06-29 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

More vulnerabilities in Apache Traffic Server

CVE-2014-3525 — Critical (CVSS 10.0): Unspecified vulnerability in Apache Traffic Server 3.x through 3.2.5, 4.x before 4.2.1.1, and 5.x before 5.0.1 has…
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CVE-2020-1944 — Critical (CVSS 9.8): There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling…
CVE-2019-17565 — Critical (CVSS 9.8): There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling…
CVE-2019-17559 — Critical (CVSS 9.8): There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling…

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