CVE Intelligence
CISA KEV Critical Insecure deserialization

CVE-2023-38203 — Adobe ColdFusion Deserialization of Untrusted Data Vulnerability

Adobe ColdFusion versions 2018u17 (and earlier), 2021u7 (and earlier) and 2023u1 (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.

Published Jul 20, 2023 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, CVE Program (cve.org) e CISA ADP, NIST National Vulnerability Database, GitHub Security Advisories · CNA: adobe

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

CISA KEV · Jan 8, 2024 R used by ransomware (CISA) ☠ Storm-0501 Detection templates (Nuclei) · 1
How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • Used in ransomware campaigns (CISA)+10
  • Exploited by 1 threat actor(s) (MITRE ATT&CK)+10
  • Public exploit/PoC (nuclei)+4
  • EPSS 97.1% (30-day exploitation probability)+15
  • Technical severity (critical)+10
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed Jan 8, 2024
EPSS FIRST
97.07%
ahead of 100% of scored CVEs · Oct 14, 2026
Affects
Adobe
Coldfusion
CVSS base
9.8
Critical · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — helpx.adobe.com (NIST National Vulnerability Database)

CISA required action CISA

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

US federal deadline: Jan 29, 2024 — passed 990 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Adobe Coldfusion).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  4. Apply the fixed version or the patch documented under Remediation.
  5. EPSS ahead of 100% of scored CVEs: prioritize it in the patch queue.
  6. Search available logs for exploit probes matching the vulnerability class (insecure deserialization), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Adobe Coldfusion version 2018-update5version 2023-update1version 2023version 2021-update7version 2021-update6version 2021-update5version 2021-update4version 2021-update3
and 20 more version 2021-update2version 2021-update1version 2021version 2018-update9version 2018-update8version 2018-update7version 2018-update6version 2018-update4version 2018-update3version 2018-update2version 2018-update17version 2018-update16version 2018-update15version 2018-update14version 2018-update13version 2018-update12version 2018-update11version 2018-update10version 2018-update1version 2018
Vulnerable NIST National Vulnerability Database
Adobe Coldfusion ≤ cf2023U1 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
9.8 CVSS 3.1 Critical 3.9 5.9 psirt@adobe.com via NIST National Vulnerability Database
9.8 CVSS 3.1 Critical — — GitHub, Inc. via GitHub Security Advisories
9.8 CVSS 3.1 Critical — — adobe via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: psirt@adobe.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-502 · Deserialization of Untrusted Data

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
Jan 8, 2024
Federal deadline
Jan 29, 2024
passed 990 day(s) ago
Ransomware use
Known

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Detection templates (Nuclei)

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

Threat actors exploiting this CVE MITRE ATT&CK

According to MITRE ATT&CK.

Storm-0501 G1053

EPSS over time FIRST

Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 97.07%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Monitor serialized objects in requests and unexpected processes spawned by the runtime.
  • Hunt retroactively in logs from before Jan 8, 2024 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPSendpoint telemetry (EDR)application logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • Affected products added · adobe/coldfusion
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · Published → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record published
    Oct 13, 2026
  • Affected products added · adobe/coldfusion
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • CVSS changed · 9.8
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Source status changed · → Published
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • 2024
  • Added to CISA KEV catalog
    Jan 7, 2024 · CISA
  • 2023
  • CVE published
    Jul 20, 2023 · adobe

Source activity

Repeated readings are counted rather than listed.

  • 3× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

4 on the record

Elsewhere on this site

Adobe
every CVE for this vendor
2024-01
what else CISA listed that month
Insecure deserialization
same class
CWE-502
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-106622 ColdFusion | Server-Side Request Forgery (SSRF) (CWE-918) 2d
  • CVE-2026-106620 ColdFusion | Incorrect Authorization (CWE-863) 2d
  • CVE-2026-106624 ColdFusion | Improper Control of Generation of Code ('Code Injection') (CWE-94) 2d
  • CVE-2026-106623 ColdFusion | Incorrect Authorization (CWE-863) 2d
  • CVE-2026-106619 ColdFusion | Improper Input Validation (CWE-20) 2d
  • CVE-2026-106618 ColdFusion | Incorrect Authorization (CWE-863) 2d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2023-38203 is "Adobe ColdFusion Deserialization of Untrusted Data Vulnerability", rated Critical. It affects Coldfusion (Adobe); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 9.8 describes technical severity. EPSS 97.07% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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