CVE & CISA-KEV Catalog

CVE-2026-47240

MEDIUM
5.8
CVSS v4
NVD

Description

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.

How to fix

Remediation Available
ruby3Rocky
Fixed in:3-main@x86_64RHSA-2026:40380
Fixed in:3-main@noarchRHSA-2026:40380
Fixed in:3-main@srcRHSA-2026:40380
Fixed in:3-main@aarch64RHSA-2026:40380
ruby3Red Hat / RHEL
Fixed in:3-main@x86_64RHSA-2026:40380
Fixed in:3-main@noarchRHSA-2026:40380
Fixed in:3-main@srcRHSA-2026:40380
Fixed in:3-main@aarch64RHSA-2026:40380

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v4 Vector

Exploitability

Attack VectorLocal
Attack ComplexityLow
Privileges RequiredNone

Impact

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/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

Exploit Intelligence

0.49%probability of exploitation in 30 days
40thpercentile

Low risk: more likely to be exploited than 40% of all known CVEs.

References

Other references1

Related Vulnerabilities

Other CWE-77 (Command Injection) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2024-3400Critical10.0100%KEV + Ransom-
CVE-2024-21887Critical9.1100%KEV + Ransom-
CVE-2023-1671Critical9.8100%KEVFix
CVE-2023-1389High8.8100%KEVFix
CVE-2021-1498Critical9.8100%KEVFix
CVE-2012-1823Critical9.8100%KEVFix

Common questions

How do I fix CVE-2026-47240?

Published advisories record a fix for 2 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2026-47240 being actively exploited?

Not that we know of. CVE-2026-47240 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.49% is the estimated probability that it will be exploited in the next 30 days. That is higher than 40% of all scored CVEs.

How severe is CVE-2026-47240?

CVE-2026-47240 has a CVSS v4 base score of 5.8, rated moderate. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2026-47240 affect?

Published advisories record a fix for ruby3 (Rocky), ruby3 (Red Hat / RHEL). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2026-47240
CVE-2026-47240 severity badge

Markdown

[![CVE-2026-47240](https://tridentstack.com/cve/badge/CVE-2026-47240.svg)](https://tridentstack.com/cve/CVE-2026-47240)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-47240"><img src="https://tridentstack.com/cve/badge/CVE-2026-47240.svg" alt="CVE-2026-47240"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it worksStart freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-23.