7.5
HIGH CVSS 3.1
CVE-2026-39820
Quadratic string concatentation in consumeComment in net/mail
Description

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

INFO

Published Date :

May 7, 2026, 8:16 p.m.

Last Modified :

May 13, 2026, 3:10 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-39820 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Golang go
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH [email protected]
Solution
Update affected software to prevent CPU and memory exhaustion vulnerabilities.
  • Update affected software to the latest version.
  • Apply vendor-provided patches.
  • Review input handling for resource limits.
Public PoC/Exploit Available at Github

CVE-2026-39820 has a 3 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-39820.

URL Resource
https://go.dev/cl/759940 Patch
https://go.dev/issue/78566 Issue Tracking
https://groups.google.com/g/golang-announce/c/qcCIEXso47M Issue Tracking Mailing List
https://pkg.go.dev/vuln/GO-2026-4986 Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-39820 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Implementação de um sistema seguro de reserva de salas (Secure SDLC) envolvendo planejamento ágil, arquitetura DevOps, modelagem de ameaças e containerização com Docker e volumes persistentes.

devsecops docker-compose hackers-do-bem secure-sdlc threat-modeling

Updated: 2 days, 4 hours ago
0 stars 0 fork 0 watcher
Born at : May 15, 2026, 11:52 p.m. This repo has been linked 1 different CVEs too.

None

HCL Shell

Updated: 1 week, 5 days ago
0 stars 0 fork 0 watcher
Born at : May 8, 2026, 3:27 p.m. This repo has been linked 5 different CVEs too.

This project provides a simple example of Spring Boot CRUD application with Postgres DB, docker-compose and LGTM Observability support

docker docker-compose grafana jdbc lgtm-stack makefile postgres spring-boot

Makefile Shell Dockerfile Java

Updated: 3 weeks, 4 days ago
0 stars 0 fork 0 watcher
Born at : Nov. 20, 2025, 7:29 p.m. This repo has been linked 51 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-39820 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-39820 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • Initial Analysis by [email protected]

    May. 13, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-770
    Added CPE Configuration OR *cpe:2.3:a:golang:go:*:*:*:*:*:*:*:* versions up to (excluding) 1.25.10 *cpe:2.3:a:golang:go:*:*:*:*:*:*:*:* versions from (including) 1.26.0 up to (excluding) 1.26.3
    Added Reference Type Go Project: https://go.dev/cl/759940 Types: Patch
    Added Reference Type Go Project: https://go.dev/issue/78566 Types: Issue Tracking
    Added Reference Type Go Project: https://groups.google.com/g/golang-announce/c/qcCIEXso47M Types: Issue Tracking, Mailing List
    Added Reference Type Go Project: https://pkg.go.dev/vuln/GO-2026-4986 Types: Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    May. 08, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
  • New CVE Received by [email protected]

    May. 07, 2026

    Action Type Old Value New Value
    Added Description Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.
    Added Reference https://go.dev/cl/759940
    Added Reference https://go.dev/issue/78566
    Added Reference https://groups.google.com/g/golang-announce/c/qcCIEXso47M
    Added Reference https://pkg.go.dev/vuln/GO-2026-4986
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.