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CVE-2026-39820

Quadratic string concatentation in consumeComment in net/mail

Published: May 7, 2026Updated: Sep 18, 2026 Sources: CVE List NVD BDUCWE-770
7.5HIGH
NVD MITRE
EPSS Score
0.8%
Top 45.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-770CWE-606

Affected Products

Go standard library
oss-project·USaka html/template, crypto/x509, golang standard library, net/http
net/mailLibraryLibrary
OSS Libraries / generic-library
golang
oss-project·US
go
OSS Libraries
The Go Project
oss-projectaka go, golang-google-protobuf, crypto
Go
OSS Libraries

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

https://go.dev/issue/78566
go.dev
https://go.dev/cl/759940
go.dev
https://groups.google.com/g/golang-announce/c/qcCIEXso47M
groups.google.com
and 94 more references View all →

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