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CVE-2023-39477: Inductive Automation Ignition ConditionRefresh Resource Exhaustion Denial-of-Service Vulnerability

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This month
HIGH 7.5REMOTEUPGRADE

CVE-2023-39477 is a high-severity flaw (CVSS 7.5) affecting ignition. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Inductive Automation Ignition ConditionRefresh Resource Exhaustion Denial-of-Service Vulnerability. This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of Inductive Automation Ignition. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of OPC UA ConditionRefresh requests. By sending a large number of requests, an attacker can consume

Why this priority

  • High severity
  • Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score7.5 (High)
Attack vectorNetwork (remote)
Attack complexityLow
Privileges neededNone
User interactionNone
EPSS exploit chance1.5% (top 25%)
CISA exploited listNo
WeaknessCWE-400
Published2024-05-03
Last modified2026-06-17
Publisher (CNA): Zero Day Initiative · Vendor: inductiveautomation

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Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

inductiveautomation ignition UPGRADE
Affected: >= 8.1.0 and < 8.1.33
Fixed in: 8.1.33
Safe to downgrade to: a release before 8.1.0
1. Check installed version
apt-cache policy ignition || rpm -q ignition || ignition --version
2. UPGRADE to 8.1.33 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade ignition
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade ignition
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 8.1.0 (Debian / Ubuntu)
apt-cache madison ignition sudo apt install ignition=<VERSION_BEFORE_8.1.0> sudo apt-mark hold ignition
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list ignition sudo dnf downgrade ignition-<VERSION_BEFORE_8.1.0> sudo dnf versionlock add ignition
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-2023-39477?

ignition: upgrade to 8.1.33. Exact commands for each OS are on this page.

Is CVE-2023-39477 being exploited?

CVE-2023-39477 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-2023-39477 affect?

CVE-2023-39477 affects ignition. Severity is high (CVSS 7.5). Inductive Automation Ignition ConditionRefresh Resource Exhaustion Denial-of-Service Vulnerability. This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of Inductive Automation Ignitio

How urgent is CVE-2023-39477?

Priority 50/100. High severity; Remotely exploitable, no login, no user action

Related CVEs

References

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