Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
🛡️
CISA KEV · ACTIVELY EXPLOITED
CRITICAL severity

CVE-2023-29300

CRITICAL

CVE-2023-29300 is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2024-01-08) and has been used in ransomware campaigns — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.

Adobe ColdFusion versions 2018u16 (and earlier), 2021u6 (and earlier) and 2023.0.0.330468 (and earlier) are affected by a Deserialization of Untrusted Data vulnerability that could…

Published
Updated
Affected
1 product
Patched
See advisory
Exploits
1 known
Exploitation data as of Oct 20, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

  • Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2024-01-08 — including use in ransomware campaigns. Federal agencies were required to remediate by 2024-01-29.
  • CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
  • A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2023-29300.

EPSS Exploitation Probability

via FIRST.org ↗
100.0%probability of exploitation in next 30 days
Very High Risk0.00%
Lower risk than most CVEs100th percentile — riskier than 100% of all scored CVEsHighest risk
91.8%94.5%97.3%100.0%93.7%100.0%Apr 26Aug 26Oct 26

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2023-29300 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Counts from FIRST.org, log-scaled.

Description

Adobe ColdFusion versions 2018u16 (and earlier), 2021u6 (and earlier) and 2023.0.0.330468 (and earlier) are affected by a Deserialization of Untrusted Data vulnerability that could result in Arbitrary code execution. Exploitation of this issue does not require user interaction.

Affected Products

1 product · 25 configurations
Application
coldfusionadobe
3 versions
201820212023
Exploits & PoCs
1

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

Detection & mitigation playbook

Vulnerability
  1. Detect

    Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).

  2. Remediation status

    No fixed release is recorded for CVE-2023-29300 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.

  3. Mitigate without a patch

    Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.

How to detect CVE-2023-29300

A community-maintained Nuclei template exists for this CVE. You can scan for it directly:

nuclei -id cve-2023-29300 -u https://target
Template
Adobe ColdFusion - Pre-Auth Remote Code Execution
Severity
critical
Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the affected system.
Remediation
Upgrade to Adobe ColdFusion version 2023.0.0.328155 or later to mitigate this vulnerability.

Template by ProjectDiscovery nuclei-templates (rootxharsh, iamnoooob, pdresearch), MIT licensed. View the full template. Scan only systems you are authorised to test.

Frequently Asked Questions

Adobe ColdFusion versions 2018u16 (and earlier), 2021u6 (and earlier) and 2023.0.0.330468 (and earlier) are affected by a Deserialization of Untrusted Data vulnerability that could result in Arbitrary code execution. Exploitation of this issue does not require user interaction.
O3 Security · Impact-Aware SCA

Is CVE-2023-29300 in your dependencies?

Find it across , including transitive dependencies.

CVE-2023-29300: Deserialization (Critical 9.8, KEV)