CVE-2026-6936: IBM i 7.6, 7.5, 7.4, and 7.3 s vulnerable to a denial-of-service attack due to uncontrolled recursion in the I

Routine

MEDIUM 6.5UPGRADE

CVE-2026-6936 is a medium-severity flaw (CVSS 6.5) 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 s vulnerable to a denial-of-service attack due to uncontrolled recursion in the Integrated Language Environment (ILE) compiler. An authenticated attacker could exploit this vulnerability by compiling specially crafted source code containing a specific combination of statements.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	6.5 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.2% (top 85%)
CISA exploited list	No
Weakness	CWE-674
Published	2026-05-27
Last modified	2026-10-14

Publisher (CNA): IBM Corporation · Vendor: ibm

Last updated 2026-10-14 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-05-27 14:17 UTCPublished CVE record published
2026-10-14 20:10 UTCUpdated Record last modified

ibm i UPGRADE

Affected: >= 7.3 and <= 7.6

Fixed in: newer than 7.6

Safe to downgrade to: a release before 7.3

1. Check installed version

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

2. UPGRADE to newer than 7.6 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade i

Note

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

3. If no update is available yet, 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

3. If no update is available yet, 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-2026-6936?

i: upgrade to newer than 7.6. Exact commands for each OS are on this page.

Is CVE-2026-6936 being exploited?

CVE-2026-6936 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-2026-6936 affect?

CVE-2026-6936 affects i. Severity is medium (CVSS 6.5). IBM i 7.6, 7.5, 7.4, and 7.3 s vulnerable to a denial-of-service attack due to uncontrolled recursion in the Integrated Language Environment (ILE) compiler. An authenticated attacker could exploit this vulnerability by compiling specially c

How urgent is CVE-2026-6936?

Priority 27/100. No elevated risk signals yet.

Related CVEs

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References

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