CVE-2026-59999: In sshd in OpenSSH before 10.4, DisableForwarding=yes was supposed to take precedence over PermitTunnel=yes, b

Q: How do I fix CVE-2026-59999?

openssh: upgrade to 10.4. Exact commands for each OS are on this page.

Q: Is CVE-2026-59999 being exploited?

CVE-2026-59999 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-2026-59999 affect?

CVE-2026-59999 affects openssh. Severity is medium (CVSS 5.9). In sshd in OpenSSH before 10.4, DisableForwarding=yes was supposed to take precedence over PermitTunnel=yes, but did not.

Q: How urgent is CVE-2026-59999?

Priority 32/100. Remotely exploitable, no login, no user action; On your watchlist

Routine

MEDIUM 5.9REMOTEWATCHLISTUPGRADE

CVE-2026-59999 is a medium-severity flaw (CVSS 5.9) affecting openssh. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

In sshd in OpenSSH before 10.4, DisableForwarding=yes was supposed to take precedence over PermitTunnel=yes, but did not.

Why this priority

Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	5.9 (Medium)
Attack vector	Network (remote)
Attack complexity	High
Privileges needed	None
User interaction	None
EPSS exploit chance	0.2% (top 95%)
CISA exploited list	No
Weakness	CWE-348
Published	2026-07-08
Last modified	2026-10-25

Publisher (CNA): MITRE · Vendor: openbsd

Last updated 2026-10-25 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-07-08 01:16 UTCPublished CVE record published
2026-10-25 20:10 UTCUpdated Record last modified

openbsd openssh UPGRADE

Affected: < 10.4

Fixed in: 10.4

Safe to downgrade to: no unaffected older release

1. Check installed version

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

2. UPGRADE to 10.4 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade openssh

Note

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

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-2026-59999?

openssh: upgrade to 10.4. Exact commands for each OS are on this page.

Is CVE-2026-59999 being exploited?

CVE-2026-59999 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-2026-59999 affect?

CVE-2026-59999 affects openssh. Severity is medium (CVSS 5.9). In sshd in OpenSSH before 10.4, DisableForwarding=yes was supposed to take precedence over PermitTunnel=yes, but did not.

How urgent is CVE-2026-59999?

Priority 32/100. Remotely exploitable, no login, no user action; On your watchlist

Software pages

OpenSSH vulnerabilities

Related CVEs

CVE-2026-60002 HIGH 7.7 UPGRADE ssh in OpenSSH before 10.4 can have a use-after-free when a server changes its host key during a key re-exchan
CVE-2026-60001 MEDIUM 6.5 UPGRADE sshd in OpenSSH before 10.4 does not always honor the minimum authentication delay.
CVE-2026-60000 LOW 3.7 UPGRADE sshd in OpenSSH before 10.4 allows remote attackers to cause a denial of service (resource consumption from ex
CVE-2026-59998 MEDIUM 4.8 UPGRADE sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAcceptorCheck has no v
CVE-2026-59995 MEDIUM 4.2 UPGRADE sftp in OpenSSH before 10.4 does not properly constrain the location of downloaded files when "sftp server:/pa

References

← Back to latest CVEs