CVE-2020-28493: Regular Expression Denial of Service (ReDoS)
Vulnerability summary
CVE-2020-28493 is a medium (CVSS 5.3) Uncontrolled Resource Consumption vulnerability in fedoraproject fedora. EPSS estimates a 3.59% chance of exploitation in the next 30 days, higher than 89.4% of scored vulnerabilities. 1 public exploit is recorded.
Not severe (CVSS 5.3, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 8 · Related 4Timeline
- 01-02-2021PublishedVulnerability first disclosed.
- 16-09-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
9 scores · 7 sources · 3 versions- OSV · AlpineEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- OSV · PypiEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- OSV · Red hatEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- OSV · DebianEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS trend
Probability
3.59%
Chance of exploitation in the next 30 days
Percentile
89%
Versus all other CVEs
30-day change
Increase +0.04 pp
From 3.55% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundExploit Reference (snyk.io)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Suse28 products
- python-Jinja2&distro=HPE Helion OpenStack 8< 2.9.6-3.6.1
- python-Jinja2&distro=SUSE Enterprise Storage 6< 2.10.1-3.10.2
- python-Jinja2&distro=SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS< 2.10.1-3.10.2
- python-Jinja2&distro=SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS< 2.10.1-3.10.2
- python-Jinja2&distro=SUSE Linux Enterprise High Performance Computing 15-ESPOS< 2.10.1-3.10.2
Mageia2 products
- python-jinja2< 2.11.3-1.mga7
- python-jinja2< 2.11.3-1.mga8
Redhat2 products
- python-jinja2< 0:2.10.1-3.el8
- python3-jinja2< 0:2.10.1-3.el8
Alpine1 product
- py3-jinja2< 1.11.3-r0
Debian1 product
- jinja2< 2.11.3-1
Fedoraproject1 product
- fedoraEOL33
Palletsprojects1 product
- jinja< 2.11.3
PyPI1 product
- jinja2< 2.11.3
Ubuntu1 product
- jinja2< 2.7.2-2ubuntu0.1~esm2 | < 2.10-1ubuntu0.18.04.1+esm1 | < 2.10.1-2ubuntu0.2 | < 2.8-1ubuntu0.1+esm1
9 vendors · 38 products
References
37 links- github.com/pallets/jinja/blob/ab81fd9c277900c85da0c322a2ff9d68a235b2e6/src/jinja2/utils.py%23L20X Refsource MISCWEBREPORTBroken Link
Show all 37 references
- github.com/pallets/jinjaPACKAGE
