CVE-2022-31129: Inefficient Regular Expression Complexity in moment
Impact
using string-to-date parsing in moment (more specifically rfc2822 parsing, which is tried by default) has quadratic (N^2) complexity on specific inputs noticeable slowdown is observed with inputs above 10k characters users who pass user-provided strings without sanity length checks to moment constructor are vulnerable to (Re)DoS attacks
Patches The problem is patched in 2.29.4, the patch can be applied to all affected versions with minimal tweaking.
Workarounds In general, given the proliferation of ReDoS attacks, it makes sense to limit the length of the user input to something sane, like 200 characters or less. I haven't seen legitimate cases of date-time strings longer than that, so all moment users who do pass a user-originating string to constructor are encouraged to apply such a rudimentary filter, that would help with this but also most future ReDoS vulnerabilities.
References There is an excellent writeup of the issue here: https://github.com/moment/moment/pull/6015#issuecomment-1152961973=
Details The issue is rooted in the code that removes legacy comments (stuff inside parenthesis) from strings during rfc2822 parsing. moment("(".repeat(500000)) will take a few minutes to process, which is unacceptable.
Other sources
A flaw was found in the Moment.js package. Users who pass user-provided strings without sanity length checks to the moment constructor are vulnerable to regular expression denial of service (ReDoS) attacks.
d3-color is vulnerable to a denial of service, caused by improper input validation. By sending a specially-crafted string that starts with the letter 'A' to the rgb() and hrc() functions, a remote attacker could exploit this vulnerability to cause a regular expression denial of service.
— IBM
moment is a JavaScript date library for parsing, validating, manipulating, and formatting dates. Affected versions of moment were found to use an inefficient parsing algorithm. Specifically using string-to-date parsing in moment (more specifically rfc2822 parsing, which is tried by default) has quadratic (N^2) complexity on specific inputs. Users may notice a noticeable slowdown is observed with inputs above 10k characters. Users who pass user-provided strings without sanity length checks to moment constructor are vulnerable to (Re)DoS attacks. The problem is patched in 2.29.4, the patch can be applied to all affected versions with minimal tweaking. Users are advised to upgrade. Users unable to upgrade should consider limiting date lengths accepted from user input.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/servicemesh-prometheusto a version that resolves this vulnerability.Fixed in 0:2.14.0-18.el8.1 - Upgrade
Upgrade
redhat/servicemesh-prometheusto a version that resolves this vulnerability.Fixed in 0:2.23.0-9.el8 - Upgrade
Upgrade
redhat/cephto a version that resolves this vulnerability.Fixed in 2:17.2.6-70.el9c - Upgrade
Upgrade
redhat/grafanato a version that resolves this vulnerability.Fixed in 0:5.2.4-6.el7 - Upgrade
Upgrade
redhat/rh-sso7-keycloakto a version that resolves this vulnerability.Fixed in 0:18.0.6-1.redhat_00001.1.el7 - Upgrade
Upgrade
redhat/rh-sso7-keycloakto a version that resolves this vulnerability.Fixed in 0:18.0.6-1.redhat_00001.1.el8 - Upgrade
Upgrade
redhat/rh-sso7-keycloakto a version that resolves this vulnerability.Fixed in 0:18.0.6-1.redhat_00001.1.el9 - Upgrade
Upgrade
redhat/cockpit-ovirtto a version that resolves this vulnerability.Fixed in 0:0.16.2-1.el8e - Upgrade
Upgrade
redhat/ovirt-engine-ui-extensionsto a version that resolves this vulnerability.Fixed in 0:1.3.5-1.el8e - Upgrade
Upgrade
nuget/Moment.jsto a version that resolves this vulnerability.Fixed in 2.29.4 - Upgrade
Upgrade
npm/momentto a version that resolves this vulnerability.Fixed in 2.29.4 - Upgrade
Upgrade
debian/node-momentto a version that resolves this vulnerability.Fixed in 2.29.1+ds-2+deb11u2Fixed in 2.29.4+ds-1 - Upgrade
Upgrade
redhat/momentto a version that resolves this vulnerability.Fixed in 2.29.4 - Upgrade
Upgrade
momentto a version that resolves this vulnerability.Fixed in 2.29.4Patch GHSA-wc69-rhjr-hc9g - Configuration
Apply a sanity length check to user-provided strings before passing them to moment constructor; limit date strings to a reasonable maximum (e.g., 200 characters or less) to mitigate (Re)DoS. Also consider rejecting/limiting extremely long inputs (e.g., the issue demonstrates moment("(".repeat(500000)) taking minutes to process).
moment user_input_length_limit_for_moment_constructor = 200 characters or less - Compensating control
If upgrading is not possible, limit date lengths accepted from user input (e.g., cap at ~200 characters) to reduce the risk of quadratic-time rfc2822 parsing leading to ReDoS.
Event History
Parent advisories
This vulnerability appears in the following advisories.
- RHSA-2022:6422
- RHSA-2022:6345
- RHSA-2022:5913
- RHSA-2022:6272
- RHSA-2022:5914
- RHSA-2022:6277
- RHSA-2022:6271
- RHSA-2022:6507
- RHSA-2022:6370
- RHSA-2022:7313
- RHSA-2023:3623
- RHSA-2023:1486
- RHSA-2022:8652
- RHSA-2022:6156
- RHSA-2022:5915
- RHSA-2023:1049
- RHSA-2023:1043
- RHSA-2023:1044
- RHSA-2023:1045
- RHSA-2022:6392
- RHSA-2022:6393
- RHSA-2023:1047
- RHSA-2022:6835
- RHSA-2022:6813
- IBM-7279901
Frequently Asked Questions
What is CVE-2022-31129?
CVE-2022-31129 is a vulnerability in the Moment.js package that allows an attacker to craft a user-provided string that can cause the parsing algorithm to become inefficient, potentially leading to denial of service.
How does CVE-2022-31129 affect moment.js?
CVE-2022-31129 affects affected versions of moment.js, specifically those that use an inefficient parsing algorithm when handling user-provided strings.
What is the severity of CVE-2022-31129?
CVE-2022-31129 has a severity rating of high, with a CVSS score of 7.5.
How do I fix CVE-2022-31129?
To fix CVE-2022-31129, upgrade to version 2.29.4 of the moment.js package.
Where can I find more information about CVE-2022-31129?
More information about CVE-2022-31129 can be found in the following references: [GitHub Commit](https://github.com/moment/moment/commit/9a3b5894f3d5d602948ac8a02e4ee528a49ca3a3), [GitHub Pull Request](https://github.com/moment/moment/pull/6015#issuecomment-1152961973), [GitHub Security Advisory](https://github.com/moment/moment/security/advisories/GHSA-wc69-rhjr-hc9g).