CVE-2021-33880

Name: CVE-2021-33880
Creator: NVD / NIST
Published: 2021-06-06T15:15:07.407+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.9/10EPSS 2.27%

Last modified Jun 17, 2026

CVE-2021-33880 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. 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.. EPSS estimates a 2.27% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

2.27%

80.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-203

Affected Software

Vendor	Product	Versions
Websockets Project	Websockets	< 9.1
Oracle	Communications Cloud Native Core Policy	1.14.0
Oracle	Communications Cloud Native Core Security Edge Protection Proxy	1.5.0
Oracle	Communications Cloud Native Core Service Communication Proxy	1.14.0
Oracle	Communications Cloud Native Core Unified Data Repository	1.14.0

References

https://github.com/aaugustin/websockets/commit/547a26b685d08cac0aa64e5e65f7867ac0ea9bc0Patch, Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
https://github.com/aaugustin/websockets/commit/547a26b685d08cac0aa64e5e65f7867ac0ea9bc0Patch, Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.htmlPatch, Third Party Advisory
https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory

Timeline

Published: Jun 6, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-33880?

How severe is CVE-2021-33880?

CVE-2021-33880 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 2.27% probability of exploitation in the next 30 days.

How do I fix CVE-2021-33880?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-33880?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST