How severe is CVE-2021-43045?

CVE-2021-43045 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 none, and availability high.

Is CVE-2021-43045 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43045?

CVE-2021-43045 affects Apache Avro. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43045?

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-2021-43045 published?

CVE-2021-43045 was published on 2022-01-06 and last updated on 2026-06-17.

CVE-2021-43045

CVE-2021-43045 is a high-severity vulnerability in Apache Avro 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-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Apache Avro
Published: 2022-01-06
Last modified: 2026-06-17

Description

A vulnerability in the .NET SDK of Apache Avro allows an attacker to allocate excessive resources, potentially causing a denial-of-service attack. This issue affects .NET applications using Apache Avro version 1.10.2 and prior versions. Users should update to version 1.11.0 which addresses this issue.

Frequently asked questions

What is CVE-2021-43045?: A vulnerability in the .NET SDK of Apache Avro allows an attacker to allocate excessive resources, potentially causing a denial-of-service attack. This issue affects .NET applications using Apache Avro version 1.10.2 and prior versions. Users should update to version 1.11.0 which addresses this issue.
How severe is CVE-2021-43045?: CVE-2021-43045 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 none, and availability high.
Is CVE-2021-43045 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43045?: CVE-2021-43045 affects Apache Avro. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43045?: 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-2021-43045 published?: CVE-2021-43045 was published on 2022-01-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:avro:*:*:*:*:*:.net:*:*

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