CVE-2021-43805: Solidus core Denial of Service Vulnerability
HIGHCVE-2021-43805 is a HIGH (CVSS 7.5) denial of service vulnerability (CWE-1333: Inefficient Regular Expression Complexity) affecting Solidus core libraries in the RubyGems ecosystem. The issue involves redos vulnerability on guest checkout email validation. Remediation is available by upgrading affected packages to version 2.11.13, 3.0.4, 3.1.4.
CVE-2021-43805 at a Glance
Security Impact
CVSS: 7.5
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
How to Fix CVE-2021-43805
To remediate this vulnerability, upgrade all affected Solidus core dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade solidus_core to 2.11.13
Upgrade solidus_core to 3.0.4
Upgrade solidus_core to 3.1.4
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for solidus_core
How to Check if You Are Affected
To determine whether your application is affected by CVE-2021-43805, inspect your project dependencies for Solidus core:
inspect dependencies for solidus_core
Analyze the terminal output to locate any version of Solidus core in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.11.13), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-1333: Inefficient Regular Expression Complexity, where the product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential. In Solidus core, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2021-43805 Affected Solidus core Versions
3 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
solidus_core
|
RubyGems |
< 2.11.13
|
2.11.13
|
|
solidus_core
|
RubyGems |
≥ 3.0.0
< 3.0.4
|
3.0.4
|
|
solidus_core
|
RubyGems |
≥ 3.1.0
< 3.1.4
|
3.1.4
|
References
Frequently Asked Questions
What is CVE-2021-43805?
Which Solidus core versions are affected?
What version fixes CVE-2021-43805?
Is solidus_core affected?
What is the CVSS score of CVE-2021-43805?
What CWE is associated with CVE-2021-43805?
How can I check RubyGems dependencies for CVE-2021-43805?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-qxmr-qxh6-2cc9",
"modified" : "2021-12-08T19:29:13Z",
"published" : "2021-12-07T22:01:47Z",
"aliases" : [ "CVE-2021-43805" ],
"summary" : "ReDos vulnerability on guest checkout email validation",
"details" : "### Impact\nDenial of service vulnerability that could be exploited during a guest checkout. The regular expression used to validate a guest order's email was subject to exponential backtracking through a fragment like `a.a.`.\n\nBefore the patch, it can be reproduced in the console like this:\n\n```ruby\nirb(main)> Spree::EmailValidator::EMAIL_REGEXP.match \"a@a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.a.@\"\nprocessing time: 54.293660s\n=> nil\n```\n\nTo reproduce in the browser, fill in the \"Customer Email\" field with that fake email address during a guest checkout. Before that, you should open the browser dev tools and change the `type` attribute for that field from `email` to `text`. After entering a fake address and pressing the \"Save & Continue\" button, the browser will take a long term to perform the request before showing an error message for the invalid address. Eventually, making the email string even longer could lead to the exhaustion of server resources.\n\n\n### Patches\nVersions 3.1.4, 3.0.4, and 2.11.13 have been patched to use a different regular expression.\n\nThere's an improbable chance that some orders in your system end up having associated an email address that is no longer valid. We've added a task to check precisely that:\n\n```bash\nbin/rails solidus:check_orders_with_invalid_email\n```\n\nThe above will print information for every affected order if any.\n\n### Workarounds\n\nIf a prompt upgrade is not an option, please, add the following to `config/application.rb`:\n\n```ruby\nconfig.after_initialize do\n Spree::EmailValidator.send(:remove_const, :EMAIL_REGEXP)\n Spree::EmailValidator::EMAIL_REGEXP = URI::MailTo::EMAIL_REGEXP\nend\n```\n\n### References\n\n- https://en.wikipedia.org/wiki/ReDoS\n- https://snyk.io/blog/redos-and-catastrophic-backtracking/\n\n### For more information\nIf you have any questions or comments about this advisory:\n* Open an [issue](https://github.com/solidusio/solidus/issues) or a [discussion](https://github.com/solidusio/solidus/discussions) in Solidus.\n* Email us at [security@solidus.io](mailto:security@soliidus.io)\n* Contact the core team on [Slack](http://slack.solidus.io/)\n",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "RubyGems",
"name" : "solidus_core"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "2.11.13"
} ]
} ]
}, {
"package" : {
"ecosystem" : "RubyGems",
"name" : "solidus_core"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.0.0"
}, {
"fixed" : "3.0.4"
} ]
} ]
}, {
"package" : {
"ecosystem" : "RubyGems",
"name" : "solidus_core"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "3.1.0"
}, {
"fixed" : "3.1.4"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/solidusio/solidus/security/advisories/GHSA-qxmr-qxh6-2cc9"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-43805"
}, {
"type" : "WEB",
"url" : "https://github.com/solidusio/solidus/commit/6be174c955fad84017ca67589c676526bc5ade71"
}, {
"type" : "WEB",
"url" : "https://github.com/solidusio/solidus/commit/9867153e01e3c3b898cdbcedd7b43375ea922401"
}, {
"type" : "WEB",
"url" : "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/solidus_core/CVE-2021-43805.yml"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/solidusio/solidus"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-1333" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2021-12-07T20:58:37Z",
"nvd_published_at" : "2021-12-07T18:15:00Z"
}
}