Net::IMAP: Command Injection via ID command argument

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

5.8 · 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 · score source

EPSS

• CVE-2026-47242: 0.18% estimated exploitation activity in the next 30 days; percentile 8.01 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Two Net::IMAP commands, #id and #enable, do not validate their arguments. Arguments to either command could be used by an attacker to inject arbitrary IMAP commands. Please note that passing untrusted inputs to these commands is usually inappropriate and expected to be uncommon. Details 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 #tos value is sent verbatim. Impact This is expected to impact very few users: use of untrusted user input for either command is expected to be very uncommon. The documentation for #enable explicitly warns that using any arguments that are not in the explicitly supported list may result in undocumented behavior. Using arbitrary untrusted user input for #enable will always…

Published by the source

9 Jun 2026, 20:31 UTC

Last modified by the source

6 Jul 2026, 22:54 UTC

Source last checked

26 Oct 2026, 15:52 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-46q3-7gv7-qmgg

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# Patch Next advisory brief: CVE-2026-47242

Advisory: Net::IMAP: Command Injection via ID command argument
IDs: CVE-2026-47242, GHSA-46q3-7gv7-qmgg
Record: https://patchnext.com/advisories/cve-2026-47242 (revision 1, source checked 26 Oct 2026, 15:52 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: net-imap 0.6.4.1, 0.5.15. A vendor fix does not mean a deployment is fixed.

## Affected components
- RubyGems net-imap: affected >= 0.6.0, <= 0.6.4; <= 0.5.14; fixed in 0.6.4.1, 0.5.15

## Suggested inspection (read-only)
- RubyGems net-imap: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on net-imap.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-46q3-7gv7-qmgg (GitHub-reviewed advisory GHSA-46q3-7gv7-qmgg lists affected ranges: RubyGems net-imap >=0.6.0 =0 <=0.5.14)

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