CVE-2020-28493

Regular Expression Denial of Service (ReDoS)

MEDIUM
5.3
CVSS Score
Published: February 1, 2021 at 07:30 PM UTC
Updated: June 17, 2026 at 03:10 AM UTC
2 products affected across 2 vendorsFedoraJinja

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Severity
MEDIUM5.3
Exploit prediction
EPSS 4%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≥ 0.0.0v < 2.11.30.0.0
Affected range stops below 2.11.3, so it looks safe — our inference, not a vendor statement

CVSS

5.3MEDIUMsnyk
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-400

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