DoS via consumePhrase in Go net/mail RFC 5322 parsing <1.26.3
CVE-2026-42499 Published on May 7, 2026

Quadratic string concatenation in consumePhrase in net/mail
Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC 5322.

NVD

Vulnerability Analysis

CVE-2026-42499 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
HIGH

Affected Versions

Go standard library net/mail:

Exploit Probability

EPSS
0.58%
Percentile
42.95%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.