CVE-2020-28493

Published: 1 February 2021

This affects the package jinja2 from 0.0.0 and before 2.11.3. The ReDoS vulnerability is mainly due to the `_punctuation_re regex` operator and its use of multiple wildcards. The last wildcard is the most exploitable as it searches for trailing punctuation. This issue can be mitigated by Markdown to format user content instead of the urlize filter, or by implementing request timeouts and limiting process memory.

Notes

Author	Note
sbeattie	regular expression DoS

Priority

Cvss 3 Severity Score

5.3

Score breakdown

Status

Package	Release	Status
jinja2 Launchpad, Ubuntu, Debian	bionic	Released (2.10-1ubuntu0.18.04.1+esm1) Available with Ubuntu Pro or Ubuntu Pro (Infra-only)
	focal	Released (2.10.1-2ubuntu0.2)
	groovy	Ignored (end of life)
	hirsute	Ignored (end of life)
	impish	Ignored (end of life)
	jammy	Not vulnerable (3.0.3-1)
	kinetic	Not vulnerable (3.0.3-1)
	lunar	Not vulnerable (3.0.3-1)
	mantic	Not vulnerable (3.0.3-1)
	trusty	Released (2.7.2-2ubuntu0.1~esm2) Available with Ubuntu Pro or Ubuntu Pro (Infra-only)
	upstream	Released (2.11.3)
	xenial	Released (2.8-1ubuntu0.1+esm1) Available with Ubuntu Pro or Ubuntu Pro (Infra-only)
	Patches: upstream: https://github.com/pallets/jinja/commit/15ef8f09b659f9100610583938005a7a10472d4d

Severity score breakdown

Parameter	Value
Base score	5.3
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	Low
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

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