Description


Progressive Robot hMailServer 6.0.0 through 6.3.5 processes several IMAP commands from a signed-in account in time quadratic in the command's length or in the number of elements it names, and can be made to hold memory out of proportion to a command. The FETCH data-item parser normalised a BODY[] section with a case-insensitive string replacement that copied the whole item per occurrence and split the item list by repeatedly copying the remainder of the command; the server's case-insensitive search compared a needle afresh at every position, so a long SEARCH TEXT key over a message cost the product of the two lengths; SEARCH message sets and the saved-result marker ($), SORT criteria, HEADER.FIELDS name lists and UID ranges were each read once per message rather than once per command; and a FETCH naming a message's sections very many times read and held every section in memory before sending any. An IMAP command may continue past one line through non-synchronizing literals, so one command can reach about eleven megabytes. The IMAP worker threads are a small pool shared with SMTP and POP3, so a signed-in user sending such commands can make the IMAP, SMTP and POP3 services stop responding (CWE-407) and can consume excessive memory (CWE-400).

Related CPE's


Could not find any relations

Weaknesses



CWE-407

CVSS impact metrics


CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

6.5 · Medium

Information


Source identifier

[email protected]

Vulnerability status

Deferred

Published

2026-10-08T12:17:16.320Z

20 hours ago

Last modified

2026-10-08T21:02:43.860Z

12 hours ago