CVE-2026-39832: When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were no

Q: How do I fix CVE-2026-39832?

crypto: upgrade to 0.52.0. Exact commands for each OS are on this page.

Q: Is CVE-2026-39832 being exploited?

CVE-2026-39832 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-39832 affect?

CVE-2026-39832 affects crypto. Severity is critical (CVSS 9.1). When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of th

Q: How urgent is CVE-2026-39832?

Priority 58/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action; On your watchlist

This month

CRITICAL 9.1REMOTEWATCHLISTUPGRADE

CVE-2026-39832 is a critical-severity flaw (CVSS 9.1) affecting crypto. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of the key on the remote host. The client now serializes all constraint extensions. Additionally, the in-memory keyring returned by NewKeyring() now rejects keys with unsupported constraint extensions instead of sil

Why this priority

Critical severity
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	9.1 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.7% (top 48%)
CISA exploited list	No
Weakness	CWE-502, CWE-281
Published	2026-05-22
Last modified	2026-09-15

Publisher (CNA): Go Project · Vendor: golang

Last updated 2026-09-15 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-05-22 04:16 UTCPublished CVE record published
2026-09-15 12:17 UTCUpdated Record last modified

golang crypto UPGRADE

Affected: < 0.52.0

Fixed in: 0.52.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy crypto || rpm -q crypto || crypto --version

2. UPGRADE to 0.52.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade crypto

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade crypto

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Exact fixes by distribution

Go · golang.org/x/crypto · FIXED · 0.52.0 · vulnerable: < 0.52.0 · source

go get golang.org/x/crypto@v0.52.0 go list -m golang.org/x/crypto

Fedora 46 · fzssh · FIXED · 1.4.0-2.fc46 · FEDORA-2026-8004fcd067 · source

sudo dnf upgrade --advisory=FEDORA-2026-8004fcd067

Ubuntu 20.04 · golang-go.crypto · FIXED · 1:0.0~git20200221.2aa609c-1ubuntu0.1~esm2

sudo apt update && sudo apt install --only-upgrade golang-go.crypto dpkg --compare-versions "$(dpkg-query -W -f='${Version}' golang-go.crypto)" ge "1:0.0~git20200221.2aa609c-1ubuntu0.1~esm2" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 22.04 · golang-go.crypto · FIXED · 1:0.0~git20211202.5770296-1ubuntu0.1~esm2

sudo apt update && sudo apt install --only-upgrade golang-go.crypto dpkg --compare-versions "$(dpkg-query -W -f='${Version}' golang-go.crypto)" ge "1:0.0~git20211202.5770296-1ubuntu0.1~esm2" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 24.04 · golang-go.crypto · FIXED · 1:0.19.0-1ubuntu0.1~esm2

sudo apt update && sudo apt install --only-upgrade golang-go.crypto dpkg --compare-versions "$(dpkg-query -W -f='${Version}' golang-go.crypto)" ge "1:0.19.0-1ubuntu0.1~esm2" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 20.04 · lxd · NOT AFFECTED

Ubuntu 20.04 · google-guest-agent · NOT AFFECTED

Debian 12 · golang-go.crypto · NO FIX YET

Debian 13 · golang-go.crypto · NO FIX YET

RHEL 10 · buildah · FIXED · buildah-1.43.1-3.el10_2

sudo dnf upgrade --advisory=RHSA-2026:36199 rpm -q buildah

RHEL 10 · podman · FIXED · podman-5.8.2-4.el10_2

sudo dnf upgrade --advisory=RHSA-2026:37072 rpm -q podman

RHEL 9 · podman · FIXED · podman-5.8.2-4.el9_8

sudo dnf upgrade --advisory=RHSA-2026:37123 rpm -q podman

RHEL 9 · buildah · FIXED · buildah-1.43.1-3.el9_8

sudo dnf upgrade --advisory=RHSA-2026:37410 rpm -q buildah

RHEL 9.6 Extended Update Support · podman · FIXED · podman-5.4.0-22.el9_6.5

sudo dnf upgrade --advisory=RHSA-2026:67450 rpm -q podman

Amazon Linux 2023 · see advisory · FIXED · ALAS2023-2026-2025 · source

sudo dnf update --advisory=ALAS2023-2026-2025

Amazon Linux 2 · see advisory · FIXED · ALAS2-2026-3844 · source

sudo yum update --advisory=ALAS2-2026-3844

Advisories and coverage

Official advisories

AlmaLinux Errata: [ALSA-2026:37410] Important: buildah security update 2026-07-13
AlmaLinux Errata: [ALSA-2026:37123] Important: podman security, bug fix, and enhancement update 2026-07-13

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-39832?

crypto: upgrade to 0.52.0. Exact commands for each OS are on this page.

Is CVE-2026-39832 being exploited?

CVE-2026-39832 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-39832 affect?

CVE-2026-39832 affects crypto. Severity is critical (CVSS 9.1). When adding a key to a remote agent constraint extensions such as restrict-destination-v00@openssh.com were not serialized in the request. Destination restrictions were silently stripped when forwarding keys, allowing unrestricted use of th

How urgent is CVE-2026-39832?

Priority 58/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action; On your watchlist

Software pages

OpenSSH vulnerabilities · Go (Golang) vulnerabilities

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References

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