CVE-2026-47242

Home/CVE/Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, wh

CVE

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Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, wh

Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to 0.6.5 and 0.5.15, when Net::IMAP#id is called with a hash argument, although the ID field value strings are correctly quoted (escaping quoted specials), they were not validated to prohibit CRLF sequences. While Net::IMAP#enable does process its arguments for aliases, it does not validate them as valid atoms (or as a list of valid atoms).

The #to_s value is sent verbatim. Arguments to either command could be used by an attacker to inject arbitrary IMAP commands. This vulnerability is fixed in 0.6.5 and 0.5.15.

Monitor

⚠ NVD has not scored this CVE yet - manual triage required (common for recent CVEs)

Sigma rules0 YARA rules0

Look this up elsewhere - one-click external pivots

NVD CVE.org CISA Exploit-DB GitHub PoC VulnCheck KEV GreyNoise

▸ How to read a CVE - triage first, then detect and patch

This page is every public fact about CVE-2026-47242, cross-linked. Its job is to answer one question fast - does this need my attention now? - and then hand you the two things you do about it. Here is how an analyst reads it.

Triage: should I act now? Four signals, and they are not interchangeable:

CVSSseverity - how bad it is IF exploited, 0-10. A high CVSS alone is not urgency; a flaw can be a perfect 10 and never actually be attacked. EPSSprobability - a model’s estimate of the chance it is exploited in the next 30 days, 0-1. This is the “will it actually happen” signal. CISA KEVconfirmed - it is being exploited in the wild right now. The strongest signal on the page; KEV beats any score. Weaponisedavailability - public exploits / PoCs, and especially Metasploit modules rated Excellent / Great. Reliable, packaged exploit code means low-skill attackers can use it today.

How they combine: KEV, or a dependable Metasploit module, means patch now regardless of CVSS. High CVSS + low EPSS + no exploit is real but not an emergency - schedule it. Low CVSS but KEV-listed still gets patched now. The verdict above already weighed these for you; this is how it got there.

Then what - two workflows:

Detectwhen you cannot patch today, follow this CVE to the ATT&CK techniques it enables, then Build a SIEM detection (the green button) - author a rule, test it in Atomic, deploy it. That buys visibility while the patch waits. PatchAffected products / packages tell you if you are exposed; Fixed versions by distribution and Vendor advisories give the exact version that closes it.

Reading order for the panels below: verdict + badges, then Public exploits / Metasploit (is it weaponised), then ATT&CK techniques + Sigma / IDS rules (can I detect it), then Affected products / packages + Fixed versions (am I exposed, what patches it), then Threat actors / IOCs (who uses it), then Scoring & timeline / references (the evidence).

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CAPEC attack patterns

Attack patterns this CVE enables - the bridge from weakness to ATT&CK technique.

CAPEC-CAPEC-136 · LDAP Injection CAPEC-CAPEC-15 · Command Delimiters CAPEC-CAPEC-183 · IMAP/SMTP Command Injection CAPEC-CAPEC-248 · Command Injection CAPEC-CAPEC-40 · Manipulating Writeable Terminal Devices CAPEC-CAPEC-43 · Exploiting Multiple Input Interpretation Layers CAPEC-CAPEC-75 · Manipulating Writeable Configuration Files CAPEC-CAPEC-76 · Manipulating Web Input to File System Calls CAPEC-CAPEC-81 · Web Server Logs Tampering

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Weakness Classification

CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')

CWE-93Improper Neutralization of CRLF Sequences ('CRLF Injection')

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Affected Packages

Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.

RubyGems net-imap MODERATE fixed in 0.6.4.1

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Related CVEs

CVEs linked to this one by a shared weakness (CWE) or affected product - joins on data already in the engine, with the reason shown per row. Not a guess.

CVE-1999-0039 webdist CGI program (webdist.cgi) in SGI IRIX allows remote attackers to execute... 1 same CWE-77 HIGH CVE-2005-2773 HP OpenView Network Node Manager 6.2 through 7.50 allows remote attackers to exe... 2 same CWE-77 CRITICAL CVE-2005-2793 PHP remote file inclusion vulnerability in welcome.php in phpLDAPadmin 0.9.6 and... same CWE-77 CVE-2007-3010 masterCGI in the Unified Maintenance Tool in Alcatel OmniPCX Enterprise Communic... 4 same CWE-77 CRITICAL CVE-2007-0892 CRLF injection vulnerability in phpMyVisites before 2.2 allows remote attackers ... same CWE-93 CVE-2014-9564 CRLF injection vulnerability in IBM Flex System EN6131 40Gb Ethernet and IB6131 ... same CWE-93 MEDIUM CVE-2014-2017 CRLF injection vulnerability in OXID eShop Professional Edition before 4.7.11 an... 1 same CWE-93 MEDIUM CVE-2014-9563 CRLF injection vulnerability in the web-based management (WBM) interface in Unif... same CWE-93 MEDIUM

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Fixed versions by distribution

The package version that resolves this CVE on each Linux distribution, from the vendor’s published security data. fixed in shows a patched version exists; open means the package is listed as affected with no fix yet.

suse sle15rmt-server open
suse sle15rmt-server-config open
suse sle15rmt-server-pubcloud open
suse sle15ruby open
suse sle15ruby-devel open

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References & Sources

Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.

https://github.com/ruby/net-imap/security/advisories/GHSA-46q3-7gv7-qmgg