CVE-2026-42792

Improper Handling of Exceptional Conditions vulnerability in Erlang OTP erts (epmd) allows an unauthenticated remote attacker to permanently terminate the Erlang Port Mapper Daemon (epmd) via connection slot exhaustion. The do_accept function in erts/epmd/src/epmd_srv.c calls epmd_cleanup_exit() when accept(2) returns EMFILE (per-process file descriptor limit reached) or ENFILE (system-wide file descriptor limit reached), rather than treating these as recoverable conditions. An attacker can exhaust epmd's file descriptor slots by holding many TCP connections open while periodically sending a single byte to reset the idle timeout, then causing accept(2) to return EMFILE, which kills the daemon. epmd has no per-source-IP connection cap, making the attack feasible from a single source. On Debian/Ubuntu default packaging the impact is amplified: the systemd unit inherits a low file descriptor soft limit, and repeated daemon deaths trigger systemd's start-rate-limit, permanently failing both epmd.service and epmd.socket and requiring manual operator intervention to recover. This issue affects OTP from OTP 17.0 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15.

CVSS

No CVSS.

References

Link	Resource
https://cna.erlef.org/cves/CVE-2026-42792.html
https://github.com/erlang/otp/commit/865d203e4a6a8f44179eced9e1428f9259e4a3bb
https://github.com/erlang/otp/security/advisories/GHSA-h6f3-hx58-xhj6
https://osv.dev/vulnerability/EEF-CVE-2026-42792
https://www.erlang.org/doc/system/versions.html#order-of-versions

Configurations

No configuration.

History

27 Jul 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-27 16:17

Updated : 2026-07-30 17:01

NVD link : CVE-2026-42792

Mitre link : CVE-2026-42792

CVE.ORG link : CVE-2026-42792

JSON object : View

Products Affected

No product.

CWE

CWE-755

Improper Handling of Exceptional Conditions

CWE-770

Allocation of Resources Without Limits or Throttling

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An attacker can exhaust epmd's file descriptor slots by holding many TCP connections open while periodically sending a single byte to reset the idle timeout, then causing accept(2) to return EMFILE, which kills the daemon. epmd has no per-source-IP connection cap, making the attack feasible from a single source.\n\nOn Debian/Ubuntu default packaging the impact is amplified: the systemd unit inherits a low file descriptor soft limit, and repeated daemon deaths trigger systemd's start-rate-limit, permanently failing both epmd.service and epmd.socket and requiring manual operator intervention to recover.\n\nThis issue affects OTP from OTP 17.0 before OTP\u00a029.0.4, OTP\u00a028.5.0.4 and OTP\u00a027.3.4.15."}], "lastModified": "2026-07-30T17:01:07.343", "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"}