How severe is CVE-2021-41973?

CVE-2021-41973 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-41973 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41973?

CVE-2021-41973 primarily affects Apache Mina. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-41973?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-41973 published?

CVE-2021-41973 was published on 2021-11-01 and last updated on 2026-06-17.

CVE-2021-41973

CVE-2021-41973 is a medium-severity vulnerability in Apache Mina with a CVSS 3.x base score of 6.5. 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-835.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Apache Mina
Published: 2021-11-01
Last modified: 2026-06-17

Description

In Apache MINA, a specifically crafted, malformed HTTP request may cause the HTTP Header decoder to loop indefinitely. The decoder assumed that the HTTP Header begins at the beginning of the buffer and loops if there is more data than expected. Please update MINA to 2.1.5 or greater.

Frequently asked questions

What is CVE-2021-41973?: In Apache MINA, a specifically crafted, malformed HTTP request may cause the HTTP Header decoder to loop indefinitely. The decoder assumed that the HTTP Header begins at the beginning of the buffer and loops if there is more data than expected. Please update MINA to 2.1.5 or greater.
How severe is CVE-2021-41973?: CVE-2021-41973 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-41973 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41973?: CVE-2021-41973 primarily affects Apache Mina. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-41973?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-41973 published?: CVE-2021-41973 was published on 2021-11-01 and last updated on 2026-06-17.

References

Affected products (13)

cpe:2.3:a:apache:mina:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:banking_payments:14.5:*:*:*:*:*:*:*
cpe:2.3:a:oracle:banking_trade_finance_process_management:14.5:*:*:*:*:*:*:*
cpe:2.3:a:oracle:banking_treasury_management:14.5:*:*:*:*:*:*:*
cpe:2.3:a:oracle:communications_cloud_native_core_console:1.9.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:customer_management_and_segmentation_foundation:18.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:customer_management_and_segmentation_foundation:19.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:flexcube_universal_banking:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:flexcube_universal_banking:14.5:*:*:*:*:*:*:*
cpe:2.3:a:oracle:fusion_middleware_common_libraries_and_tools:12.2.1.3.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:fusion_middleware_common_libraries_and_tools:12.2.1.4.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:fusion_middleware_common_libraries_and_tools:14.1.1.0.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:oss_support_tools:2.12.42:*:*:*:*:*:*:*

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