Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2022-40023

26
FAUCET Score

CVE-2022-40023 is a Regular Expression Denial of Service (ReDoS) vulnerability affecting Sqlalchemy Mako versions prior to 1.2.2, as well as babelplugin and linguaplugin, when the Lexer class is used for parsing. This vulnerability carries a CVSS score of 7.5 (HIGH), indicating that an unauthenticated attacker can remotely trigger a denial of service with low attack complexity. There is currently no evidence of active exploitation, publicly available exploit code, or significant community discussion surrounding this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
< 1.2.2CPE matchmatch criteria
cpe:2.3:a:sqlalchemy:mako:*:*:*:*:*:*:*:*
10.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

7.5HIGH

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
3.6
CvssVersion
3.1

Exploit Intelligence

EPSS Score
1.72%
Probability of exploitation in next 30 days
EPSS Percentile
75.1%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0172 is in the 58th percentile among its peer group of 51,506 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (12)

github_advisorypatch availablevia nvd_reference
View patch
microsoftpatch availablevia msrc
Product: cm1 python-mako 1.0.7-5 on CBL Mariner 1.0Fixed in: 1.0.7-5
microsoftpatch availablevia msrc
Product: 18622-16820Fixed in: 1.0.7-5
microsoftpatch availablevia msrc
Product: 18623-16823Fixed in: 1.2.2-1
microsoftpatch availablevia msrc
Product: cbl2 python-mako 1.2.2-1 on CBL Mariner 2.0Fixed in: 1.2.2-1
pippatch availablevia ghsa
Product: makoFixed in: 1.2.2
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 9Fixed in: python-mako-0:1.1.4-6.el9
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 8Fixed in: python-mako-0:1.0.6-14.el8
View patch
redhatno patchvia redhat_api
Product: Red Hat Openshift Container Storage 4Fixed in: python-pecan
redhatno patchvia redhat_api
Product: Red Hat Openshift Data Foundation 4Fixed in: python-pecan
redhatno patchvia redhat_api
Product: Red Hat Quay 3Fixed in: quay/quay-rhel8
redhatend of lifevia redhat_api
Product: Red Hat Enterprise Linux 8Fixed in: resource-agents

Vendor Advisories (3)

pipGHSA-v973-fxgf-6xhphigh

mako is vulnerable to Regular Expression Denial of Service

Sep 16, 2022
microsoft2022-Sep/CVE-2022-40023Important

Sqlalchemy mako before 1.2.2 is vulnerable to Regular expression Denial of Service when using the Lexer class to parse. This also affects babelplugin and linguaplugin.

Sep 13, 2022
redhatCVE-2022-40023Moderate

python-mako: REDoS in Lexer class

Sep 7, 2022

References

lists.debian.org / debian-lts-announce/2025/12/msg00004.html
github.com / sqlalchemy/mako/blob/c2f392e0be52dc67d1b9770ab8cce6a9c736d547/mako/ext/extract.py
ExploitThird Party Advisory
github.com / sqlalchemy/mako/commit/925760291d6efec64fda6e9dd1fd9cfbd5be068c
Patch
github.com / sqlalchemy/mako/issues/366
Issue TrackingPatch
lists.debian.org / debian-lts-announce/2022/09/msg00026.html
Mailing ListThird Party Advisory
pyup.io / posts/pyup-discovers-redos-vulnerabilities-in-top-python-packages
ExploitThird Party Advisory
pyup.io / vulnerabilities/CVE-2022-40023/50870
Third Party Advisory