CVE-2026-107572

Progressive Robot hMailServer versions 6.2.24 through 6.3.5 are vulnerable to a Denial of Service (DoS) condition due to inefficient complexity in Sieve filter evaluation. The vulnerability arises from a backtracking descent during :matches pattern matching, where execution time grows exponential...

CVE-2026-107572 Inefficient Regular Expression Complexity in hMailServer

Inefficient complexity in the Sieve filter evaluation of Progressive Robot hMailServer 6.2.24 through 6.3.5 allows an authenticated account holder to make the mail services unavailable with their own filter. A ':matches' pattern was matched by a backtracking descent whose time grew with the match...