CVE-2026-42499: CWE-407: Inefficient Algorithmic Complexity in Go standard library net/mail
CVE-2026-42499 is a vulnerability in the Go standard library's net/mail package where pathological inputs can cause a denial of service (DoS) by exploiting inefficient algorithmic complexity in the consumePhrase function during email address parsing as per RFC 5322. This vulnerability affects versions up to 1. 26. 0-0. There is no CVSS score or vendor advisory indicating a patch or mitigation. No known exploits are reported in the wild.
AI Analysis
Technical Summary
The Go standard library net/mail package contains an inefficient algorithmic complexity issue (CWE-407) in the consumePhrase function used to parse email addresses according to RFC 5322. Maliciously crafted inputs can trigger excessive resource consumption leading to denial of service. The vulnerability affects Go versions up to 1.26.0-0. No official remediation or patch information is currently available.
Potential Impact
An attacker can cause a denial of service by providing specially crafted email address inputs that exploit the inefficient parsing algorithm, potentially leading to resource exhaustion in applications using the vulnerable net/mail package. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, consider implementing input validation or limiting resource usage when parsing email addresses with the net/mail package to mitigate potential DoS risks.
CVE-2026-42499: CWE-407: Inefficient Algorithmic Complexity in Go standard library net/mail
Description
CVE-2026-42499 is a vulnerability in the Go standard library's net/mail package where pathological inputs can cause a denial of service (DoS) by exploiting inefficient algorithmic complexity in the consumePhrase function during email address parsing as per RFC 5322. This vulnerability affects versions up to 1. 26. 0-0. There is no CVSS score or vendor advisory indicating a patch or mitigation. No known exploits are reported in the wild.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Go standard library net/mail package contains an inefficient algorithmic complexity issue (CWE-407) in the consumePhrase function used to parse email addresses according to RFC 5322. Maliciously crafted inputs can trigger excessive resource consumption leading to denial of service. The vulnerability affects Go versions up to 1.26.0-0. No official remediation or patch information is currently available.
Potential Impact
An attacker can cause a denial of service by providing specially crafted email address inputs that exploit the inefficient parsing algorithm, potentially leading to resource exhaustion in applications using the vulnerable net/mail package. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, consider implementing input validation or limiting resource usage when parsing email addresses with the net/mail package to mitigate potential DoS risks.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Go
- Date Reserved
- 2026-04-28T00:21:12.791Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fcf0c1cbff5d86102bd5e3
Added to database: 5/7/2026, 8:06:25 PM
Last enriched: 5/7/2026, 8:21:38 PM
Last updated: 5/7/2026, 9:07:02 PM
Views: 3
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