CVE-2026-75538 Erlang CVE debrief

Who should care

Defenders managing Erlang OTP systems, especially those using the inet driver with {packet,4} mode, should assess exposure and verify the need for updates or compensating controls.

Why it matters

Defenders should prioritize verifying exposure of Erlang OTP systems using the inet driver with {packet,4} mode and assess the need for updates or compensating controls due to potential system crashes and availability impacts.

• Potential system crashes due to overflow of the receive buffer
• Need for verification of exposure and potential updates to OTP versions
• Possible impact on system availability and stability

Technical summary

The vulnerability involves a signed overflow in packet length calculation when using the inet driver with {packet,4} mode in Erlang OTP. This can overflow the receive buffer into the VM allocator area, potentially causing a crash. The issue affects various OTP versions, including those before OTP 27.3.4.17, OTP 28.5.0.6, and OTP 29.0.6. Defenders should prioritize verifying exposure of Erlang OTP systems, especially those using the inet driver with {packet,4} mode, and assess the need for updates or compensating controls.

Defensive priority

Defenders should prioritize verifying exposure of Erlang OTP systems, especially those using the inet driver with {packet,4} mode, and assess the need for updates or compensating controls.

Recommended defensive actions

• Verify exposure of Erlang OTP systems using the inet driver with {packet,4} mode
• Assess the need for updates to OTP 27.3.4.17, OTP 28.5.0.6, or OTP 29.0.6
• Implement compensating controls for affected systems
• Review 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 NVD entry provide details on the vulnerability, but the scope of affected versions before OTP 17.0 is unknown. The issue involves a signed overflow in packet length calculation when using the inet driver with {packet,4} mode in Erlang OTP, which can overflow the receive buffer into the VM allocator area. Defenders should verify exposure of Erlang OTP systems, especially those using the inet driver with {packet,4} mode, and assess the need for updates or compensating controls.

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.