CVE-2021-43082 | heap-buffer-overflow with stats-over-http plugin

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.

Published: 2021-11-03 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-43082 is rated High Risk (68.9/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 2.33%). EPSS rose +1.23% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-43082

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.10% 2.33% +1.23%
2 2025-12-28 0.80% 1.10% +0.31%
3 2025-12-27 — 0.80% —

Full EPSS history (22 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-43082

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2021-43082

OS Trackers for CVE-2021-43082

vendor priority summary link
debian unimportant CVE-2021-43082 unimportant priority: Debian including 1 source packages (trafficserver), 3 status rows across 3 suites (bookworm, bullseye, sid): resolved 3. https://security-tracker.debian.org/tracker/CVE-2021-43082
ubuntu medium CVE-2021-43082 medium priority: Ubuntu including 1 source packages (trafficserver), 15 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 8, not-affected 6, released 1. https://ubuntu.com/security/CVE-2021-43082

Affected software / configurations for CVE-2021-43082

Vendor Product Version Raw CPE
apache traffic_server >= 8.0.0, <= 8.1.2 cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
apache traffic_server >= 9.0.0, <= 9.1.0 cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*

References for CVE-2021-43082

URL Tags
https://lists.apache.org/thread/k01797hyncx53659wr3o72s5cvkc3164 Mailing List Patch Vendor Advisory
cvelogic Threat Intelligence