{"id":"CVE-2021-43805","aliases":["EUVD-2021-2575","GHSA-qxmr-qxh6-2cc9"],"status":"published","title":"ReDos vulnerability on guest checkout email validation","description":"Solidus is a free, open-source ecommerce platform built on Rails. Versions of Solidus prior to 3.1.4, 3.0.4, and 2.11.13 have a denial 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.` Versions 3.1.4, 3.0.4, and 2.11.13 have been patched to use a different regular expression. The maintainers added a check for email addresses that are no longer valid that will print information about any affected orders that exist. If a prompt upgrade is not an option, a workaround is available. It is possible to edit the file `config/application.rb` manually (with code provided by the maintainers in the GitHub Security Advisory) to check email validity.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.01449,"percentile":0.73719,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-1333"],"published":"2021-12-07T17:25:09Z","modified":"2026-10-20T10:55:03Z","fixes":[{"ecosystem":"RubyGems","package":"solidus_core","fixed_in":["2.11.13","3.0.4","3.1.4"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"RubyGems","package":"solidus_core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.11.13"}]}]},{"source":"ghsa","ecosystem":"RubyGems","package":"solidus_core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.0.0"},{"fixed":"3.0.4"}]}]},{"source":"ghsa","ecosystem":"RubyGems","package":"solidus_core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.1.0"},{"fixed":"3.1.4"}]}]},{"source":"osv","ecosystem":"RubyGems","package":"solidus_core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.11.13"}]}],"versions":["1.0.0","1.0.0.pre","1.0.0.pre2","1.0.0.pre3","1.0.0.rc1","1.0.0.rc2","1.0.1","1.0.2","1.0.3","1.0.4","1.0.5","1.0.6","1.0.7","1.1.0","1.1.0.beta1","1.1.0.pre1","1.1.0.pre2","1.1.1","1.1.2","1.1.3","1.1.4","1.2.0","1.2.0.beta1","1.2.0.rc1","1.2.0.rc2","1.2.1","1.2.2","1.2.3","1.3.0","1.3.0.beta1","1.3.0.rc1","1.3.0.rc2","1.3.1","1.3.2","1.4.0","1.4.0.beta1","1.4.0.rc1","1.4.1","1.4.2","2.0.0","2.0.0.beta1","2.0.0.rc1","2.0.1","2.0.2","2.0.3","2.1.0","2.1.0.beta1","2.1.0.rc1","2.1.1","2.10.0","2.10.0.beta1","2.10.1","2.10.2","2.10.3","2.10.5","2.11.0","2.11.1","2.11.10","2.11.11","2.11.12","2.11.2","2.11.3","2.11.4","2.11.5","2.11.6","2.11.7","2.11.8","2.11.9","2.2.0","2.2.0.beta1","2.2.0.rc1","2.2.1","2.2.2","2.3.0","2.3.0.beta1","2.3.0.rc1","2.3.0.rc2","2.3.0.rc3","2.3.1","2.4.0","2.4.0.beta1","2.4.0.rc1","2.4.1","2.4.2","2.5.0","2.5.0.beta1","2.5.0.beta2","2.5.0.rc1","2.5.1","2.5.2","2.6.0","2.6.0.rc1","2.6.1","2.6.2","2.6.3","2.6.4","2.6.5","2.6.6","2.7.0","2.7.1","2.7.2","2.7.3","2.7.4","2.8.0","2.8.1","2.8.2","2.8.3","2.8.4","2.8.5","2.8.6","2.9.0","2.9.0.rc.1","2.9.1","2.9.2","2.9.3","2.9.4","2.9.5","2.9.6"]},{"source":"osv","ecosystem":"RubyGems","package":"solidus_core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.0.0"},{"fixed":"3.0.4"}]}],"versions":["3.0.0","3.0.1","3.0.2","3.0.3"]},{"source":"osv","ecosystem":"RubyGems","package":"solidus_core","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.1.0"},{"fixed":"3.1.4"}]}],"versions":["3.1.0","3.1.1","3.1.2","3.1.3"]}],"products":[{"vendor":"nebulab","product":"solidus"},{"vendor":"solidusio","product":"solidus"}],"references":[{"url":"https://github.com/solidusio/solidus/security/advisories/GHSA-qxmr-qxh6-2cc9","tags":["x_refsource_CONFIRM","x_transferred","Exploit","Mitigation","Third Party Advisory","evidence","web"]},{"url":"https://github.com/solidusio/solidus/commit/9867153e01e3c3b898cdbcedd7b43375ea922401","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://github.com/solidusio/solidus/commit/6be174c955fad84017ca67589c676526bc5ade71","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-43805","tags":["advisory"]},{"url":"https://github.com/rubysec/ruby-advisory-db/blob/master/gems/solidus_core/CVE-2021-43805.yml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-qxmr-qxh6-2cc9"},{"url":"https://github.com/solidusio/solidus","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2021-43805","title":"ReDos vulnerability on guest checkout email validation","description":"Solidus is a free, open-source ecommerce platform built on Rails. Versions of Solidus prior to 3.1.4, 3.0.4, and 2.11.13 have a denial 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.` Versions 3.1.4, 3.0.4, and 2.11.13 have been patched to use a different regular expression. The maintainers added a check for email addresses that are no longer valid that will print information about any affected orders that exist. If a prompt upgrade is not an option, a workaround is available. It is possible to edit the file `config/application.rb` manually (with code provided by the maintainers in the GitHub Security Advisory) to check email validity.","status":"published","published":"2021-12-07T17:25:09Z","modified":"2024-08-04T04:03:08.816Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-1333"],"updated_at":"2026-11-02T14:32:57.033395Z"}],"euvd":[{"id":"EUVD-2021-2575","description":"Solidus is a free, open-source ecommerce platform built on Rails. Versions of Solidus prior to 3.1.4, 3.0.4, and 2.11.13 have a denial 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.` Versions 3.1.4, 3.0.4, and 2.11.13 have been patched to use a different regular expression. The maintainers added a check for email addresses that are no longer valid that will print information about any affected orders that exist. If a prompt upgrade is not an option, a workaround is available. It is possible to edit the file `config/application.rb` manually (with code provided by the maintainers in the GitHub Security Advisory) to check email validity.","status":"published","published":"2021-12-07T17:25:09Z","modified":"2024-08-04T04:03:08Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-03T03:24:13.772922Z"}],"ghsa":[{"id":"GHSA-qxmr-qxh6-2cc9","title":"ReDos vulnerability on guest checkout email validation","description":"### 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)\u003e 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=\u003e 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 \u0026 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","status":"published","published":"2021-12-07T22:01:47Z","modified":"2023-05-04T19:59:42Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-1333"],"updated_at":"2026-11-02T14:36:52.310293Z"}],"nvd":[{"id":"CVE-2021-43805","description":"Solidus is a free, open-source ecommerce platform built on Rails. Versions of Solidus prior to 3.1.4, 3.0.4, and 2.11.13 have a denial 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.` Versions 3.1.4, 3.0.4, and 2.11.13 have been patched to use a different regular expression. The maintainers added a check for email addresses that are no longer valid that will print information about any affected orders that exist. If a prompt upgrade is not an option, a workaround is available. It is possible to edit the file `config/application.rb` manually (with code provided by the maintainers in the GitHub Security Advisory) to check email validity.","status":"published","published":"2021-12-07T18:15:07.407Z","modified":"2026-06-17T04:11:28.453Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"secondary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-1333"],"updated_at":"2026-11-02T14:07:01.811115Z"}],"osv":[{"id":"CVE-2021-43805","description":"Solidus is a free, open-source ecommerce platform built on Rails. Versions of Solidus prior to 3.1.4, 3.0.4, and 2.11.13 have a denial 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.` Versions 3.1.4, 3.0.4, and 2.11.13 have been patched to use a different regular expression. The maintainers added a check for email addresses that are no longer valid that will print information about any affected orders that exist. If a prompt upgrade is not an option, a workaround is available. It is possible to edit the file `config/application.rb` manually (with code provided by the maintainers in the GitHub Security Advisory) to check email validity.","status":"published","published":"2021-12-07T18:15:07.407Z","modified":"2026-10-20T10:55:03.30621847Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:21.877444Z"},{"id":"GHSA-qxmr-qxh6-2cc9","title":"ReDos vulnerability on guest checkout email validation","description":"### 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)\u003e 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=\u003e 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 \u0026 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","status":"published","published":"2021-12-07T22:01:47Z","modified":"2026-07-08T06:28:36.700655909Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-1333"],"updated_at":"2026-11-02T15:46:55.122811Z"}]}}