CVE-2026-42258

net-imap: Command Injection via unvalidated Symbol inputs

CVSS score

5.8

EPSS probability

%1.3

Risk score

0.1

Published

5 mo ago

Overview Public Exploits (0)Newsroom Vulnerability Timeline

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2026-42258 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

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, symbol arguments to commands are vulnerable to a CRLF Injection / IMAP Command injection via Symbol arguments passed to IMAP commands. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-42258 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

ID	VENDOR	PRODUCT	ACTION
1	ruby	net-imap	View
2	ruby-lang	net\	View
3	ruby-lang	net\	View
4	ruby-lang	net\	View

Total affected vendors: 2|Products: 4

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCORE	VERSION	SEVERITY	VECTOR	SOURCE
7.1	CVSS V31	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N	NVD
7.1	CVSS V3_1	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:N	CVE ADP
5.8	CVSS V40	MEDIUM	CVSS:4.0/AV:L/AC:H/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	NVD
5.8	CVSS V4_0	MEDIUM	CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N	CVE CNA
5.3	CVSS V31	MEDIUM	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L	NVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.

Restrict access to internet-facing services and apply network segmentation.

Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.

Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-42258 is associated with the following CWEs:

CWE-77: Common Weakness Enumeration Entry CWE-77 CWE-93: Common Weakness Enumeration Entry CWE-93

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-42258 weaknesses.

CAPEC-66: SQL Injection CAPEC-126: Path Traversal CAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureYerel erişim

PermissionsGerekmiyor

User—

Official Sources and Advisories

https://github.com/ruby/net-imap/security/advisories/GHSA-75xq-5h9v-w6pxvendor-advisory https://github.com/ruby/net-imap/releases/tag/v0.4.24vendor-advisory https://github.com/ruby/net-imap/releases/tag/v0.5.14vendor-advisory https://github.com/ruby/net-imap/releases/tag/v0.6.4vendor-advisory https://access.redhat.com/errata/RHSA-2026:33462nvd https://access.redhat.com/errata/RHSA-2026:33512nvd https://access.redhat.com/errata/RHSA-2026:33514nvd https://access.redhat.com/errata/RHSA-2026:33515nvd https://access.redhat.com/errata/RHSA-2026:33540nvd https://access.redhat.com/errata/RHSA-2026:33565nvd

CVSS Vector Radar Chart

5.8 / 10

Vulnerability Scoring Details

CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

Attack VectorLocal

Attack ComplexityHigh

Privileges RequiredNone required

User InteractionP

Confidentiality (Gizlilik)High

Integrity (Bütünlük)P

Availability (Erişilebilirlik)Low

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

ruby

ruby-lang

Weakness Type (CWE & CAPEC)

CWE-77 CWE-93

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