CVE-2025-12995: High Brute Force Flaw in Medtronic CareLink Network

CVE-2025-12995 is a high severity flaw (CVSS 8.1) in Medtronic CareLink Network. An unauthenticated remote attacker could brute force an API endpoint to work out a valid password under certain circumstances. The record scopes it to versions before December 4, 2025. Check Medtronic's security bulletin for the fix and your next steps.

What's affected

The record lists one product, Medtronic CareLink Network, and gives the affected range as "before December 4, 2025". That is a date, not a version number, so there is no package version to compare against. The record does not say how the fix was delivered. Medtronic's security bulletin is the reference it points to, and it is the place to confirm whether the change is applied for you or needs action on your side.

The weakness is CWE-307, improper restriction of excessive authentication attempts. The CVSS vector is CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Two details matter. No privileges and no user interaction are needed, which is why the score is high. Attack complexity is rated high, because the description says the attack works only "under certain circumstances".

The record's kev flag is false, so CISA has not listed this as exploited in the wild, and the record does not claim exploitation. I could not load the Medtronic bulletin page when preparing this post, so anything beyond the record should be taken from the bulletin itself.

How to check if you're exposed

Most readers of this post will not run CareLink infrastructure themselves, so the check is mostly about who in your organisation owns the relationship with the vendor.

• Identify whether your organisation uses CareLink Network and who administers the account.
• Open the Medtronic security bulletin and read the affected and remediated statements.
• If you have an API gateway, proxy or log pipeline in front of any CareLink integration, look for a high volume of failed sign in responses from a single source. A burst of failures against one endpoint is the pattern that a guessing attack produces.

# example: count failed auth responses per client address in an nginx style log
awk '$9==401 || $9==403 {print $1}' access.log | sort | uniq -c | sort -rn | head

Adjust the log field numbers to your own format. This is a generic check for repeated failures, not a test for this specific flaw.

What to do now

1. Find your owner for the Medtronic relationship and open the vendor security bulletin with them.
2. Confirm in writing whether the fix dated December 4, 2025 applies to your tenant, or whether any customer side step is needed.
3. Ask which lockout, rate limit or monitoring controls apply to the API endpoint in your setup.
4. Make sure accounts that can reach the service use long, unique passwords and, where the product supports it, a second factor.
5. Alert on bursts of failed sign ins from a single source in whatever logs you control.
6. Record the answer in your risk register with the date you checked, so the review is not repeated from scratch next quarter.

Why it matters

Brute force protection is a basic control. When an endpoint accepts unlimited guesses, the strength of every password behind it becomes the only defence. The weakness class, CWE-307, covers missing or weak limits on repeated authentication attempts, such as no lockout, no delay and no rate limit.

The high attack complexity rating keeps this from scoring even higher, but the potential impact is rated high on confidentiality, integrity and availability, which is why the final score is 8.1. In a healthcare setting those three words carry weight, so a vendor bulletin deserves a real read rather than a skim.

Quick check

Sources

• Safeguard Gold entry for CVE-2025-12995
• https://www.medtronic.com/en-us/e/product-security/security-bulletins/carelink-network-vulnerabilities.html

Last reviewed: 19 October 2026.