CVE-2026-47240CWE-77CWE-93

Net::IMAP: Command Injection via non-synchronizing literal in "raw" argument

Medium · published June 22, 2026

CVSS v4.0
5.8
EPSS
1%
Percentile
57.1
In the wild
Unconfirmed
What it is

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, several Net::IMAP commands accept a "raw data" argument that is sent verbatim after validation to prevent command injection. However, if a server does not support non-synchronizing literals, it may still be possible to inject arbitrary IMAP commands inside non-synchronizing literals. A server without support for non-synchronizing literals may interpret the "+}\r\n" as the end of a malformed command line and respond with a tagged BAD. In that case, the contents of the literal will be interpreted as one or more new pipelined commands, allowing a CRLF command injection attack to succeed. This affects criteria for #search and #uid_search; search_keys for #sort, #thread, #uid_sort, and #uid_thread; and attr for #fetch and #uid_fetch. This vulnerability is fixed in 0.6.5 and 0.5.15.

The record
Technical detail
CVSS v4.0
5.8 · MEDIUM
Vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N
EPSS
0.00831 · 57.1th percentile
Weaknesses
CWE-77 · Improper Neutralization of Special Elements used in a Command ('Command Injection'); CWE-93 · Improper Neutralization of CRLF Sequences ('CRLF Injection')
Published
2026-06-22T20:17Z
EPSS history
Timeline
  • 22 JUN 20:17Z
    Net::IMAP: Command Injection via non-synchronizing literal in "raw" argument
    cvelistv5