CVE-2026-47240
Description
A flaw was found in Net::IMAP, a Ruby library that provides Internet Message Access Protocol (IMAP) client functionality. This vulnerability allows a remote attacker to inject arbitrary IMAP commands. This is possible when an IMAP server does not support non-synchronizing literals, leading to the misinterpretation of data as new commands. This command injection could enable unauthorized actions on the IMAP server.
Statement
This Moderate flaw in the Net::IMAP Ruby library allows for command injection against IMAP servers that lack support for non-synchronizing literals. An attacker could exploit this by providing specially crafted input, leading to the execution of arbitrary IMAP commands and potential unauthorized actions. This risk is primarily present in deployments interacting with older or non-standard IMAP server configurations.
Mitigation
Explicitly validate user-controlled inputs to prevent embedded non-synchronizing literals unless the server supports them. For a simpler, more cautious approach: all embedded literals can be unconditionally prohibited, by checking that string inputs do not contain any CR or LF bytes.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.1 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | High | N/A | N/A |
| Availability Impact | Low | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Application Data
Frequently Asked Questions
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