CVE-2023-5404· NVD / CVE Program· CNA Honeywell

Server receiving a malformed message can cause a pointer to be overwritten which can result in a remote code execution or failure.

Noroxi assessment

Priority: Monitor (action score 32/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.72% (FIRST EPSS); higher than 53.4% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. Special conditions such as timing or configuration are required.
Fixed version: Honeywell Experion Server 510.2 HF14, 511.5 TCU4 HF4, 520.1 TCU5.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Honeywell Experion Server 510.2 HF14, 511.5 TCU4 HF4, 520.1 TCU5 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Server receiving a malformed message can cause a pointer to be overwritten which can result in a remote code execution or failure. See Honeywell Security Notification for recommendations on upgrading and versioning.

HighCVSS 8.1 · v3.1—No exploit Fix available

Published: Apr 17, 2024
Updated: Jun 17, 2026
EPSS: 0.7% · 53th percentile
CWE: CWE-122

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 32 / 40 · 8.1 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.7%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · Honeywell: 8.1; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
honeywell	experion server	cpe:2.3:a:honeywell:experion_server

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Honeywell). Independent of NVD's CPE analysis and usually ahead of it.

Honeywell Experion Server
- 520.2 and later · up to and including 520.2 TCU4affected · semverfixed in 520.2 TCU4 HF1
- 510.1 and later · up to and including 510.2 HF13affected · semverfixed in 510.2 HF14
- 520.1 and later · up to and including 520.1 TCU4affected · semverfixed in 520.1 TCU5
- 511.1 and later · up to and including 511.5 TCU4 HF3affected · semverfixed in 511.5 TCU4 HF4
- 520.2 and later · up to and including 520.2 TCU4affected · semverfixed in 520.2 TCU4 HF2
- 511.1 and later · up to and including 511.5 TCU4 HF3affected · semverfixed in 511.5 TCU4 HF4
- 520.1 and later · up to and including 520.1 TCU4affected · semverfixed in 520.1 TCU5
- 520.2 and later · up to and including 520.2 TCU4affected · semverfixed in 520.2 TCU4 HF2
- 520.1 and later · up to and including 520.1 TCU4affected · semverfixed in 520.1 TCU5
- 520.2 TCU4 HFR2 and later · up to and including 511.5 TCU4 HF3affected · semverfixed in 511.5 TCU4 HF4

Same product

honeywell: all records

Other highest-scoring records for the same primary product.

CVE-2023-5403Server hostname translation to IP address manipulation which could lead to an attacker performing remote code execution or causing a failure
32Monitor
CVE-2023-5401Server receiving a malformed message based on a using the specified key values can cause a stack overflow vulnerability which could lead to
32Monitor
CVE-2023-5400Server receiving a malformed message based on a using the specified key values can cause a heap overflow vulnerability which could lead to a
32Monitor

Published before and after this one in the same product

← EarlierCVE-2023-5397Apr 17, 2024 · Server receiving a malformed message to create a new connection could lead to an attacker performing remote code execution or causing a fail
32Monitor
← EarlierCVE-2023-5398Apr 17, 2024 · Server receiving a malformed message based on a list of IPs resulting in heap corruption causing a denial of service.
23Monitor
Later →CVE-2023-5405Apr 17, 2024 · Server information leak for the CDA Server process memory can occur when an error is generated in response to a specially crafted message.
23Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Honeywell Experion Server	510.2 HF14	Vendor (CNA)
Honeywell Experion Server	511.5 TCU4 HF4	Vendor (CNA)
Honeywell Experion Server	520.1 TCU5	Vendor (CNA)
Honeywell Experion Server	520.2 TCU4 HF1	Vendor (CNA)
Honeywell Experion Server	520.2 TCU4 HF2	Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2023-54000 days apartServer receiving a malformed message based on a using the specified key values can cause a heap overflow vulnerability which could lead to a
32Monitor
CVE-2023-24474279 days apartServer deserialization missing boundary checks - heap overflow in communication between server and controller
30Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).