How severe is CVE-2021-33880?

CVE-2021-33880 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-33880 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-2021-33880?

CVE-2021-33880 primarily affects Websockets Project Websockets. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33880?

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

When was CVE-2021-33880 published?

CVE-2021-33880 was published on 2021-06-06 and last updated on 2026-06-17.

CVE-2021-33880

CVE-2021-33880 is a medium-severity vulnerability in Websockets Project Websockets with a CVSS 3.x base score of 5.9. 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-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 2.6
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Websockets Project Websockets
Published: 2021-06-06
Last modified: 2026-06-17

Description

The aaugustin websockets library before 9.1 for Python has an Observable Timing Discrepancy on servers when HTTP Basic Authentication is enabled with basic_auth_protocol_factory(credentials=...). An attacker may be able to guess a password via a timing attack.

Frequently asked questions

What is CVE-2021-33880?: The aaugustin websockets library before 9.1 for Python has an Observable Timing Discrepancy on servers when HTTP Basic Authentication is enabled with basic_auth_protocol_factory(credentials=...). An attacker may be able to guess a password via a timing attack.
How severe is CVE-2021-33880?: CVE-2021-33880 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-33880 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-2021-33880?: CVE-2021-33880 primarily affects Websockets Project Websockets. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33880?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33880 published?: CVE-2021-33880 was published on 2021-06-06 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:websockets_project:websockets:*:*:*:*:*:python:*:*
cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.14.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:communications_cloud_native_core_security_edge_protection_proxy:1.5.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:communications_cloud_native_core_service_communication_proxy:1.14.0:*:*:*:*:*:*:*
cpe:2.3:a:oracle:communications_cloud_native_core_unified_data_repository:1.14.0:*:*:*:*:*:*:*

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