CVE-2026-42245: CWE-407: Inefficient Algorithmic Complexity in ruby net-imap
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, Net::IMAP::ResponseReader has quadratic time complexity when reading large responses containing many string literals. A hostile server can send responses which are crafted to exhaust the client's CPU for a denial of service attack. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
AI Analysis
Technical Summary
The vulnerability in Ruby's net-imap library (CVE-2026-42245) arises from inefficient algorithmic complexity (CWE-407) in the ResponseReader when handling large IMAP responses with many string literals. This results in quadratic time complexity, allowing a malicious IMAP server to craft responses that exhaust the client's CPU resources, causing a denial of service. The flaw affects versions before 0.4.24, 0.5.14, and 0.6.4. The issue has been patched in these versions.
Potential Impact
A hostile IMAP server can exploit this vulnerability to cause excessive CPU consumption on the client running vulnerable net-imap versions, leading to denial of service. The CVSS 4.0 base score is 2.3, indicating low severity. There are no known exploits in the wild.
Mitigation Recommendations
This vulnerability has been patched in net-imap versions 0.4.24, 0.5.14, and 0.6.4. Users should upgrade to these or later versions to remediate the issue. Patch status is not explicitly stated in a vendor advisory but the fixed versions are known. No additional mitigation steps are indicated.
CVE-2026-42245: CWE-407: Inefficient Algorithmic Complexity in ruby net-imap
Description
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, Net::IMAP::ResponseReader has quadratic time complexity when reading large responses containing many string literals. A hostile server can send responses which are crafted to exhaust the client's CPU for a denial of service attack. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in Ruby's net-imap library (CVE-2026-42245) arises from inefficient algorithmic complexity (CWE-407) in the ResponseReader when handling large IMAP responses with many string literals. This results in quadratic time complexity, allowing a malicious IMAP server to craft responses that exhaust the client's CPU resources, causing a denial of service. The flaw affects versions before 0.4.24, 0.5.14, and 0.6.4. The issue has been patched in these versions.
Potential Impact
A hostile IMAP server can exploit this vulnerability to cause excessive CPU consumption on the client running vulnerable net-imap versions, leading to denial of service. The CVSS 4.0 base score is 2.3, indicating low severity. There are no known exploits in the wild.
Mitigation Recommendations
This vulnerability has been patched in net-imap versions 0.4.24, 0.5.14, and 0.6.4. Users should upgrade to these or later versions to remediate the issue. Patch status is not explicitly stated in a vendor advisory but the fixed versions are known. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-25T05:37:12.118Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69ff93c0cbff5d86106e4579
Added to database: 5/9/2026, 8:06:24 PM
Last enriched: 5/9/2026, 8:21:41 PM
Last updated: 5/10/2026, 7:51:46 AM
Views: 15
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