Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-42257— net-imap: Command Injection via "raw" arguments to multiple commands

Quick assessment

Affected
ruby net-imap
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Net::IMAP是Ruby开源的一个消息访问协议的 Ruby 客户端 api。 Net::IMAP 0.4.24之前版本、0.5.14之前版本和0.6.4之前版本存在命令注入漏洞，该漏洞源于多个Net::IMAP命令接受未经验证或转义的原始字符串参数，可能导致CRLF注入和IMAP命令注入。

AI Predicted 9.8 Difficulty: Easy EPSS 0.52% · P42

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application

Affected Version Matrix 3

VendorProduct Version RangeStatus
ruby net-imap < 0.4.24 affected
>= 0.5.0, < 0.5.14 affected
>= 0.6.0, < 0.6.4 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-42257

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
net-imap: Command Injection via "raw" arguments to multiple commands
Source: CVE Program / CVE List V5
Vulnerability Description
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.4.24, 0.5.14, and 0.6.4, several Net::IMAP commands accept a raw string argument that is sent to the server without validation or escaping. If this string is derived from user-controlled input, it may contain contain CRLF sequences, which an attacker can use to inject arbitrary IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
Source: CVE Program / CVE List V5
CVSS Information
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
Source: CVE Program / CVE List V5
Vulnerability Type
对CRLF序列的转义处理不恰当(CRLF注入)
Source: CVE Program / CVE List V5
Vulnerability Title
Net::IMAP 命令注入漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Net::IMAP是Ruby开源的一个消息访问协议的 Ruby 客户端 api。 Net::IMAP 0.4.24之前版本、0.5.14之前版本和0.6.4之前版本存在命令注入漏洞，该漏洞源于多个Net::IMAP命令接受未经验证或转义的原始字符串参数，可能导致CRLF注入和IMAP命令注入。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
ruby net-imap < 0.4.24 -

II. Public POCs for CVE-2026-42257

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-42257

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-42257 (1)

Vendor Advisories for CVE-2026-42257 (1)

Vendor Pages for CVE-2026-42257 (1)

Other References for CVE-2026-42257 (1)

Same Patch Batch · ruby · 2026-05-09 · 5 CVEs total

CVE-2026-42246 7.6 HIGH net-imap vulnerable to STARTTLS stripping via invalid response timing
CVE-2026-42258 5.8 MEDIUM net-imap: Command Injection via unvalidated Symbol inputs
CVE-2026-42245 net-imap: Quadratic complexity when reading response literals
CVE-2026-42256 net-imap: Denial of service via high iteration count for `SCRAM-*` authentication

IV. Related Vulnerabilities

Same product: net-imap
Same vendor: ruby
Same weakness: CWE-93

V. Comments for CVE-2026-42257

No comments yet

Leave a comment