CVE-2026-5846Network attack vector

Controller takeover via hard-coded TLS private keys

Published Jul 30, 2026 · Updated Jul 30, 2026

Hard-coded TLS keys in Watchfire BC controllers allow remote attackers to install malicious firmware and gain full controller control. The firmware stores a shared RSA private key and its self-signed X.509 certificate in plaintext patch binaries, then uses that credential to authenticate and encrypt HTTPS management traffic. Exploitation requires access to a patch binary, network reachability to the built-in web interface, and user interaction; the published impact excludes service interruption.

CVSS severity7.6
High
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Hard-coded TLS keys in Watchfire BC controllers allow remote attackers to install malicious firmware and gain full controller control. The firmware stores a shared RSA private key and its self-signed X.509 certificate in plaintext patch binaries, then uses that credential to authenticate and encrypt HTTPS management traffic. Exploitation requires access to a patch binary, network reachability to the built-in web interface, and user interaction; the published impact excludes service interruption.

The record

CVE
CVE-2026-5846
Published
Jul 30, 2026
Updated
Jul 30, 2026
Vendor
Watchfire Signs
Product
BC550
Classifications
CWE-321, T1552.004
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Jul 30, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 30, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=12.30

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

Watchfire Signs · BC550version=12.30
Watchfire Signs · BC760DCversion=12.39
Watchfire Signs · BC760version=12.38; version=13.00
Watchfire Signs · BC750version=11.33; version=12.35

Published CVSS scores

7.6ICS-CERTCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
5.7ICS-CERTCVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-321Use of Hard-coded Cryptographic Key
T1552.004Unsecured Credentials: Private Keys

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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