CVE-2026-47240
published 2026-06-22CVE-2026-47240: 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…
PriorityP338medium5.8CVSS 4.0
AVLACLATPPRNUIPVCNVIHVALSCNSINSANEXCRXIRXARXMAVXMACXMATXMPRXMUIXMVCXMVIXMVAXMSCXMSIXMSAXSXAUXRXVXREXUX
EPSS
0.49%
38.5th percentile
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.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| ruby | net-imap | < 0.5.15 | 0.5.15 |
| ruby | net-imap | — | — |
| ruby | net-imap | >= 0 < 0.5.15 | 0.5.15 |
| ruby | net-imap | >= 0.6.0 < 0.6.4.1 | 0.6.4.1 |
CVSS provenance
nvdv4.05.8MEDIUMCVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
ghsa9.8CRITICAL
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VulDB
ruby net-imap up to 0.5.14 Net::IMAP command injection (GHSA-8p34-64r3-mwg8 / Nessus ID 323667)
vuldb·2026-06-30·CVSS 5.8
CVE-2026-47240 [MEDIUM] ruby net-imap up to 0.5.14 Net::IMAP command injection (GHSA-8p34-64r3-mwg8 / Nessus ID 323667)
A vulnerability identified as critical has been detected in ruby net-imap up to 0.5.14. Affected by this vulnerability is the function Net::IMAP. Performing a manipulation results in command injection.
This vulnerability is identified as CVE-2026-47240. The attack is only possible with local access. There is not any exploit available.
You should upgrade the affected component.
GHSA
Net::IMAP: Command Injection via non-synchronizing literal in "raw" argument
ghsa·2026-06-09·CVSS 9.8
CVE-2026-47240 [CRITICAL] CWE-77 Net::IMAP: Command Injection via non-synchronizing literal in "raw" argument
Net::IMAP: Command Injection via non-synchronizing literal in "raw" argument
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.
### Details
Raw data arguments support embedded literal values, both synchronizing and non-synchronizing. Non-synchronizing literals can only be safely sent when the server advertises any of the `LITERAL+`, `LITERAL-`, or `IMAP4rev2` capabilities. But raw data arguments do not verify server support for non-synchronizing literals prior to sending.
Servers without support for non-synchronizing literals could handle them in several d
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-06-22
Published