Description
Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. Prior to versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4, a man-in-the-middle attacker can cause Net::IMAP#starttls to return "successfully", without starting TLS. This issue has been patched in versions 0.3.10, 0.4.24, 0.5.14, and 0.6.4.
Metrics
CVSS 3.1 7.4/10
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| ruby | net-imap | < 0.3.10; >= 0.4.0, < 0.4.24; >= 0.5.0, < 0.5.14; >= 0.6.0, < 0.6.4 |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | — |
| Red Hat | Red Hat Enterprise Linux 8 | — |
| Red Hat | Red Hat Enterprise Linux 8 | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | — |
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | — |
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | — |
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9 | — |
| Red Hat | Red Hat Enterprise Linux 9 | — |
| Red Hat | Red Hat Enterprise Linux 9 | — |
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — |
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | — |
| Red Hat | Red Hat Hardened Images | — |
| Red Hat | Red Hat Hardened Images | — |
| Red Hat | Red Hat Hardened Images | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat 3scale API Management Platform 2 | — |
| Red Hat | Red Hat Enterprise Linux 6 | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — |
References
- https://github.com/ruby/net-imap/commit/0ede4c40b1523dfeaf95777b2678e54cc0fd9618Patch
- https://github.com/ruby/net-imap/commit/24a4e770b43230286a05aa2a9746cdbb3eb8485ePatch
- https://github.com/ruby/net-imap/commit/97e2488fb5401a1783bddd959dde007d9fbce42cPatch
- https://github.com/ruby/net-imap/commit/f79d35bf5833f186e81044c57c843eda30c873daPatch
- https://github.com/ruby/net-imap/releases/tag/v0.3.10Release Notes
- https://github.com/ruby/net-imap/releases/tag/v0.4.24Release Notes
- https://github.com/ruby/net-imap/releases/tag/v0.5.14Release Notes
- https://github.com/ruby/net-imap/security/advisories/GHSA-vcgp-9326-pqcpMitigation, Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:33462
- https://access.redhat.com/errata/RHSA-2026:33512
- https://access.redhat.com/errata/RHSA-2026:33514
- https://access.redhat.com/errata/RHSA-2026:33515
- https://access.redhat.com/errata/RHSA-2026:33540
- https://access.redhat.com/errata/RHSA-2026:33551
- https://access.redhat.com/errata/RHSA-2026:33552
- https://access.redhat.com/errata/RHSA-2026:33565
- https://access.redhat.com/errata/RHSA-2026:33576
- https://access.redhat.com/errata/RHSA-2026:33577
- https://access.redhat.com/errata/RHSA-2026:33630
- https://access.redhat.com/errata/RHSA-2026:33721
- https://access.redhat.com/errata/RHSA-2026:34076
- https://access.redhat.com/errata/RHSA-2026:35834
- https://access.redhat.com/errata/RHSA-2026:35866
- https://access.redhat.com/errata/RHSA-2026:35867
- https://access.redhat.com/errata/RHSA-2026:35895
- https://access.redhat.com/errata/RHSA-2026:36099
- https://access.redhat.com/errata/RHSA-2026:37238
- https://access.redhat.com/errata/RHSA-2026:37397
- https://access.redhat.com/security/cve/CVE-2026-42246
- https://bugzilla.redhat.com/show_bug.cgi?id=2468499
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42246.json
Timeline
- Published
- May 9, 2026
- Last modified
- Aug 24, 2026
- NVD status
- Modified