CVE-2025-12899 zephyrproject-rtos CVE debrief

Who should care

Zephyr users, network administrators, and security teams should assess exposure and verify versions. Zephyr users with network exposure should prioritize this vulnerability and take necessary actions to mitigate the risk. Network administrators and security teams should review network configurations, monitor network traffic, and plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Why it matters

CVE-2025-12899 is a medium-severity vulnerability in Zephyr's network stack that could lead to information leaks. Zephyr users, especially those with network exposure, should assess their exposure, verify versions, and monitor network traffic.

• Potential information leak through out-of-bounds memory read
• Network traffic monitoring and filtering may be necessary
• Version verification and patching are required

Technical summary

The Zephyr network stack misclassifies an IPv4 packet containing ICMP type 128 as an ICMPv6 Echo Request, leading to an out-of-bounds memory read. This vulnerability could lead to information leaks through out-of-bounds memory reads. Zephyr users, especially those with network exposure, should assess their exposure, verify versions, and monitor network traffic. The vulnerability is a medium-severity issue that requires attention from Zephyr users, network administrators, and security teams. Affected product deployments should be reviewed for exposure, and owners should be assigned for follow-up.

Defensive priority

Medium priority for Zephyr users, especially those with network exposure.

Recommended defensive actions

• Review network configurations and exposure
• Verify Zephyr version and assess vulnerability
• Monitor network traffic for suspicious activity
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed

Evidence notes

The CVE record and source item provide details on the vulnerability, but affected versions and remediation require verification from official sources. Zephyr users should verify their versions and assess exposure. The vulnerability could lead to information leaks through out-of-bounds memory reads. Defenders should review network configurations, verify Zephyr versions, and monitor network traffic for suspicious activity.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.