The imap_header function in the IMAP functionality for PHP before 4.3.0 allows remote attackers to cause a denial of service via an e-mail message with a large number of "To" addresses, which triggers an error in the rfc822_write_address function.
Severity
Medium 5.0
Published
31 Dec 2002
Last changed
16 Jun 2026
Added to UpHeron
14 Oct 2026
Exploit chance
1.4% in the next 30 daysHigher than 71% of CVEs. EPSS by FIRST, 12 Nov 2026