CVE-2026-42258

MEDIUMNVD 5.35.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.3 under NVD CVSS v3. EPSS exploit probability: 0.9%, top 44% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Trending — 3 sources updated this week
5.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 1%CVSS: 5.3Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
5.3
EG Score
5.3(medium)
EPSS
52.6%
KEV
Not listed

Published

May 9, 2026

Last Modified

July 6, 2026

Advisory Details (4)

Auto-updated Jun 21, 2026
Patch available. Sources: github_release, github.
github Patch Available

Command Injection via unvalidated Symbol inputs · Advisory · ruby/net-imap · GitHub

https://github.com/ruby/net-imap/security/advisories/GHSA-75xq-5h9v-w6px
github_release Patch Available

v0.6.4

Patch available: ruby/net-imap v0.6.4

https://github.com/ruby/net-imap/releases/tag/v0.6.4
github_release Patch Available

v0.5.14

Patch available: ruby/net-imap v0.5.14

https://github.com/ruby/net-imap/releases/tag/v0.5.14
github_release Patch Available

v0.4.24

Patch available: ruby/net-imap v0.4.24

https://github.com/ruby/net-imap/releases/tag/v0.4.24

Vendor Advisories for CVE-2026-42258(14)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
RubyGems(1)
PackageVulnerable rangeFixed inDependents
net-imap0.1.0 ... 0.4.9.1 (45 versions)0.4.24—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 10× in last 7d / 92× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 169 total refreshes for this CVE.

  1. 2026-07-06 16:27 UTCEPSS rescore
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 13:51 UTCNVD updateCVSS v3 → 5.3 · severity → MEDIUM
  4. 2026-07-06 13:07 UTCMITRE cvelistV5CVSS v3 → 7.1 · severity → HIGH
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-05 02:30 UTCEPSS rescore
  8. 2026-07-04 06:31 UTCEPSS rescore
  9. 2026-07-01 15:06 UTCEPSS rescore
  10. 2026-06-30 23:22 UTCEPSS rescore
  11. 2026-06-29 14:06 UTCEPSS rescore
  12. 2026-06-28 14:07 UTCEPSS rescore
  13. 2026-06-28 04:56 UTCEPSS rescore
  14. 2026-06-28 03:43 UTCEG score recompute
  15. 2026-06-27 03:08 UTCEPSS rescore
  16. 2026-06-26 21:11 UTCEG score recompute▼ 4.50
  17. 2026-06-26 19:41 UTCNVD updateCVSS v3 → 5.3 · severity → MEDIUM
  18. 2026-06-26 05:46 UTCEG score recompute
  19. 2026-06-25 13:49 UTCEPSS rescore
  20. 2026-06-25 13:49 UTCEPSS rescore
  21. 2026-06-24 14:05 UTCEPSS rescore
  22. 2026-06-23 21:33 UTCEPSS rescore
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  1. 2026-06-21 14:56 UTCEPSS rescore
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  3. 2026-06-19 19:25 UTCEPSS rescore
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  7. 2026-06-17 05:42 UTCEG score recompute
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  11. 2026-06-15 17:49 UTCEPSS rescore
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  20. 2026-06-13 23:00 UTCEPSS rescore
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  22. 2026-06-13 02:27 UTCEG score recompute
  23. 2026-06-12 23:12 UTCEPSS rescore
  24. 2026-06-12 23:12 UTCEPSS rescore
  25. 2026-06-12 22:44 UTCEG score recompute
  26. 2026-06-12 18:32 UTCEG score recompute
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  33. 2026-06-11 14:00 UTCEPSS rescore
  34. 2026-06-11 12:00 UTCEG score recompute
  35. 2026-06-11 08:15 UTCEG score recompute
  36. 2026-06-11 04:31 UTCEG score recompute
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  38. 2026-06-10 22:18 UTCEPSS rescore
  39. 2026-06-10 21:04 UTCEG score recompute
  40. 2026-06-10 17:20 UTCEG score recompute
  41. 2026-06-10 13:36 UTCEG score recompute
  42. 2026-06-10 13:22 UTCEPSS rescore
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  44. 2026-06-10 09:53 UTCEG score recompute
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  47. 2026-06-09 22:41 UTCEG score recompute
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  50. 2026-06-09 11:31 UTCEG score recompute
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  56. 2026-06-08 14:17 UTCEPSS rescore
  57. 2026-06-08 14:17 UTCEPSS rescore
  58. 2026-06-08 11:10 UTCEG score recompute
  59. 2026-06-08 07:24 UTCEG score recompute
  60. 2026-06-08 03:40 UTCEG score recompute
  61. 2026-06-07 23:57 UTCEG score recompute
  62. 2026-06-07 20:14 UTCEG score recompute
  63. 2026-06-07 16:30 UTCEG score recompute
  64. 2026-06-07 15:25 UTCEPSS rescore
  65. 2026-06-07 15:25 UTCEPSS rescore
  66. 2026-06-07 12:46 UTCEG score recompute
  67. 2026-06-07 09:02 UTCEG score recompute
  68. 2026-06-07 05:18 UTCEG score recompute
  69. 2026-06-07 01:35 UTCEG score recompute
  70. 2026-06-06 21:50 UTCEG score recompute
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  72. 2026-06-06 14:22 UTCEG score recompute
  73. 2026-06-06 13:47 UTCEPSS rescore
  74. 2026-06-06 13:47 UTCEPSS rescore
  75. 2026-06-06 10:38 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-42258?
CVE-2026-42258 is a medium vulnerability published on May 9, 2026. 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…
When was CVE-2026-42258 disclosed?
CVE-2026-42258 was first published in the National Vulnerability Database on May 9, 2026, with the most recent update on July 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-42258 actively exploited?
CVE-2026-42258 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 52.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-42258?
CVE-2026-42258 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-42258?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-42258, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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