path-to-regexp vulnerable to Denial of Service via sequential optional groups
cve-program · CVE-2026-4926
PublishedImpact: A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. Patches: Fixed in version 8.4.0. Workarounds: Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.
Read the publisher's advisoryeuvd · EUVD-2026-16324
PublishedImpact: A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. Patches: Fixed in version 8.4.0. Workarounds: Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.
Read the publisher's advisorynvd · CVE-2026-4926
PublishedImpact: A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. Patches: Fixed in version 8.4.0. Workarounds: Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.
Read the publisher's advisoryosv · GHSA-j3q9-mxjg-w52f
Published### Impact A bad regular expression is generated any time you have multiple sequential optional groups (curly brace syntax), such as `{a}{b}{c}:z`. The generated regex grows exponentially with the number of groups, causing denial of service. ### Patches Fixed in version 8.4.0. ### Workarounds Limit the number of sequential optional groups in route patterns. Avoid passing user-controlled input as route patterns.
Read the publisher's advisoryAffected versions, risk and source history
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path-to-regexp vulnerable to Denial of Service via sequential optional groups
osv · GHSA-j3q9-mxjg-w52f · Published
path-to-regexp vulnerable to Denial of Service via sequential optional groups
cve-program · CVE-2026-4926 · Published