CVE-2026-16859: IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to obtain sensitive information due to an out-of-bo

Routine

MEDIUM 5.3REMOTEDOWNGRADE

CVE-2026-16859 is a medium-severity flaw (CVSS 5.3) affecting i. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to obtain sensitive information due to an out-of-bounds read.

Why this priority

Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.4% (top 66%)
CISA exploited list	No
Weakness	CWE-125
Published	2026-08-13
Last modified	2026-08-17

Publisher (CNA): IBM Corporation · Vendor: ibm

Last updated 2026-08-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-08-13 20:17 UTCPublished CVE record published
2026-08-17 15:07 UTCUpdated Record last modified

ibm i DOWNGRADE

Affected: 7.3 · 7.4 · 7.5 · 7.6

Fixed in: no fixed release known

Safe to downgrade to: a release before 7.3

1. Check installed version

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

2. No fixed release: DOWNGRADE to a release before 7.3 (Debian / Ubuntu)

apt-cache madison i sudo apt install i=<VERSION_BEFORE_7.3> sudo apt-mark hold i

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list i sudo dnf downgrade i-<VERSION_BEFORE_7.3> sudo dnf versionlock add i

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

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-2026-16859?

i: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2026-16859 being exploited?

CVE-2026-16859 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-2026-16859 affect?

CVE-2026-16859 affects i. Severity is medium (CVSS 5.3). IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to obtain sensitive information due to an out-of-bounds read.

How urgent is CVE-2026-16859?

Priority 32/100. Remotely exploitable, no login, no user action

Related CVEs

CVE-2026-2311 MEDIUM 6.4 MITIGATE IBM i 7.6, 7.5, 7.4, 7.3, and 7.2 s vulnerable to privilege escalation caused by an invalid IBM i Web Administ
CVE-2026-7870 HIGH 8.8 MITIGATE IBM i 7.6, 7.5, 7.4, and 7.3 could allow a user to gain elevated privileges due to an unqualified library call
CVE-2026-9072 HIGH 8.1 UPGRADE IBM WebSphere Application Server and IBM WebSphere Application Server Liberty - when using Intelligent Managem
CVE-2026-10852 MEDIUM 5.9 MITIGATE IBM WebSphere Application Server and IBM WebSphere Application Server Liberty are vulnerable to denial of serv
CVE-2026-8858 HIGH 7.5 UPGRADE IBM WebSphere Application Server and IBM WebSphere Application Server Liberty are vulnerable to remote code ex

References

← Back to latest CVEs