Ubuntu 20.04 LTS / 20.10 / 21.04 : Eventlet vulnerability (USN-4956-1)

medium Nessus Plugin ID 149520
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Synopsis

The remote Ubuntu host is missing a security update.

Description

The remote Ubuntu 20.04 LTS / 20.10 / 21.04 host has a package installed that is affected by a vulnerability as referenced in the USN-4956-1 advisory.

- Eventlet is a concurrent networking library for Python. A websocket peer may exhaust memory on Eventlet side by sending very large websocket frames. Malicious peer may exhaust memory on Eventlet side by sending highly compressed data frame. A patch in version 0.31.0 restricts websocket frame to reasonable limits. As a workaround, restricting memory usage via OS limits would help against overall machine exhaustion, but there is no workaround to protect Eventlet process. (CVE-2021-21419)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected python3-eventlet package.

See Also

https://ubuntu.com/security/notices/USN-4956-1

Plugin Details

Severity: Medium

ID: 149520

File Name: ubuntu_USN-4956-1.nasl

Version: 1.2

Type: local

Agent: unix

Published: 5/17/2021

Updated: 5/17/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2021-21419

VPR

Risk Factor: Low

Score: 1.4

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, cpe:/o:canonical:ubuntu_linux:20.10, cpe:/o:canonical:ubuntu_linux:21.04, p-cpe:/a:canonical:ubuntu_linux:python3-eventlet

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 5/17/2021

Vulnerability Publication Date: 5/7/2021

Reference Information

CVE: CVE-2021-21419

USN: 4956-1