CVE-2026-39821 · cross-distro fix matrix

CVE-2026-39821: It was discovered that Go Networking incorrectly handled certain

Affects 2 Linux releases across 4 (distro × package) combinations. First disclosed: 2026-05-22.

CVSS v3:CRITICAL · 9.6(NVD-published)

Fix per ecosystem

Each block below is a distro release where CVE-2026-39821 has a known fix. Run the listed command on that distro to remediate.

Ubuntu bionic

Source: Ubuntu USN

golang-golang-x-net-dev→ fixed in1:0.0+git20170629.c81e7f2+dfsg-2ubuntu0.1~esm3USN-8416-1
```
sudo apt-get install --only-upgrade -y golang-golang-x-net-dev
```
golang-go.net-dev→ fixed in1:0.0+git20170629.c81e7f2+dfsg-2ubuntu0.1~esm3USN-8416-1
```
sudo apt-get install --only-upgrade -y golang-go.net-dev
```

Ubuntu focal

Source: Ubuntu USN

golang-golang-x-net-dev→ fixed in1:0.0+git20190811.74dc4d7+dfsg-1ubuntu0.1~esm3USN-8416-1
```
sudo apt-get install --only-upgrade -y golang-golang-x-net-dev
```
golang-go.net-dev→ fixed in1:0.0+git20190811.74dc4d7+dfsg-1ubuntu0.1~esm3USN-8416-1
```
sudo apt-get install --only-upgrade -y golang-go.net-dev
```

Are YOU affected by CVE-2026-39821?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan View on NVD

Continuous monitoring beats manual checking

CVE-2026-39821dropped silently in your distro's update channel. Every new CVE is the same story. StackPatch runs the matcher hourly against all 5 sources and emails the exact remediation when something new applies to one of your servers. $99 lifetime, 50 founder seats, 30-day refund.

See StackPatch ($99 lifetime)