How severe is CVE-2018-4939?

CVE-2018-4939 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2018-4939?

Affected package information for CVE-2018-4939 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2018-4939?

No fixed version has been published for CVE-2018-4939 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2018-4939 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2018-4939, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2018-4939?

CVE-2018-4939 has an EPSS (Exploit Prediction Scoring System) score of 50.5%, placing it in the 98th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2018-4939 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2018-4939 (Adobe ColdFusion Deserialization of Untrusted Data Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2021-11-03. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-05-03. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2018-4939?

CVE-2018-4939 is classified as Deserialization of Untrusted Data (CWE-502). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Which products and versions are affected by CVE-2018-4939?

CVE-2018-4939 affects adobe coldfusion (2 versions, e.g. 11.0, 2016). Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2018-4939 published, and has it been updated?

CVE-2018-4939 was published on May 19, 2018 and was last updated on October 23, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2021-11-03 — agencies required to remediate by 2022-05-03

CVE-2018-4939

CRITICAL

Adobe ColdFusion Update 5 and earlier versions, ColdFusion 11 Update 13 and earlier versions have an exploitable Deserialization of Untrusted Data vulnerability. Successful exploitation…

Published

May 19, 2018

Updated

Oct 23, 2025

Affected

0 pkgs

Patched

None yet

Exploits

1 known

EPSS Exploitation Probability

via FIRST.org ↗

50.5%probability of exploitation in next 30 days

High Risk98th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

Adobe ColdFusion Update 5 and earlier versions, ColdFusion 11 Update 13 and earlier versions have an exploitable Deserialization of Untrusted Data vulnerability. Successful exploitation could lead to arbitrary code execution.

Affected Products

1 product · 20 configurations

Application

coldfusionadobe

2 versions

11.02016

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Adobe ColdFusion Update 5 and earlier versions, ColdFusion 11 Update 13 …

cisa.govCISAJul 2021

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2018-4939 in your stack?

O3 detects CVE-2018-4939 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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