How severe is CVE-2021-43082?

CVE-2021-43082 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43082 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43082?

CVE-2021-43082 affects Apache Traffic Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43082?

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

When was CVE-2021-43082 published?

CVE-2021-43082 was published on 2021-11-03 and last updated on 2026-06-17.

CVE-2021-43082

CVE-2021-43082 is a critical-severity vulnerability in Apache Traffic Server with a CVSS 3.x base score of 9.8. 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-120.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Apache Traffic Server
Published: 2021-11-03
Last modified: 2026-06-17

Description

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in the stats-over-http plugin of Apache Traffic Server allows an attacker to overwrite memory. This issue affects Apache Traffic Server 9.1.0.

Frequently asked questions

What is CVE-2021-43082?: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in the stats-over-http plugin of Apache Traffic Server allows an attacker to overwrite memory. This issue affects Apache Traffic Server 9.1.0.
How severe is CVE-2021-43082?: CVE-2021-43082 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43082 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43082?: CVE-2021-43082 affects Apache Traffic Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43082?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-43082 published?: CVE-2021-43082 was published on 2021-11-03 and last updated on 2026-06-17.

References

https://lists.apache.org/thread/k01797hyncx53659wr3o72s5cvkc3164

Affected products (1)

cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*

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