{"containers":{"cna":{"affected":[{"cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["epmd_srv"],"packageName":"erts","packageURL":"pkg:otp/erts?repository_url=https:%2F%2Fgithub.com%2Ferlang%2Fotp&vcs_url=git%20https:%2F%2Fgithub.com%2Ferlang%2Fotp.git","product":"OTP","programFiles":["epmd/src/epmd_srv.c"],"programRoutines":[{"name":"do_accept"}],"repo":"https://github.com/erlang/otp","vendor":"Erlang","versions":[{"changes":[{"at":"17.0.4","status":"unaffected"},{"at":"16.4.0.4","status":"unaffected"},{"at":"15.2.7.11","status":"unaffected"}],"lessThan":"*","status":"affected","version":"6.0","versionType":"otp"}]},{"collectionURL":"https://github.com","cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["epmd_srv"],"packageName":"erlang/otp","packageURL":"pkg:github/erlang/otp","product":"OTP","programFiles":["erts/epmd/src/epmd_srv.c"],"programRoutines":[{"name":"do_accept"}],"repo":"https://github.com/erlang/otp","vendor":"Erlang","versions":[{"changes":[{"at":"29.0.4","status":"unaffected"},{"at":"28.5.0.4","status":"unaffected"},{"at":"27.3.4.15","status":"unaffected"}],"lessThan":"*","status":"affected","version":"17.0","versionType":"otp"},{"lessThan":"865d203e4a6a8f44179eced9e1428f9259e4a3bb","status":"affected","version":"07b8f441ca711f9812fad9e9115bab3c3aa92f79","versionType":"git"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*","versionEndExcluding":"27.3.4.15","vulnerable":true},{"criteria":"cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*","versionEndExcluding":"28.5.0.4","versionStartIncluding":"28.0","vulnerable":true},{"criteria":"cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*","versionEndExcluding":"29.0.4","versionStartIncluding":"29.0","vulnerable":true}],"negate":false,"operator":"OR"}],"operator":"AND"}],"credits":[{"lang":"en","type":"finder","value":"Ryan Moore"},{"lang":"en","type":"remediation developer","value":"John Högberg"}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"Improper Handling of Exceptional Conditions vulnerability in Erlang OTP <tt>erts</tt> (<tt>epmd</tt>) allows an unauthenticated remote attacker to permanently terminate the Erlang Port Mapper Daemon (epmd) via connection slot exhaustion.<p>The <tt>do_accept</tt> function in <tt>erts/epmd/src/epmd_srv.c</tt> calls <tt>epmd_cleanup_exit()</tt> when <tt>accept(2)</tt> returns <tt>EMFILE</tt> (per-process file descriptor limit reached) or <tt>ENFILE</tt> (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 <tt>accept(2)</tt> to return <tt>EMFILE</tt>, which kills the daemon. epmd has no per-source-IP connection cap, making the attack feasible from a single source.</p><p>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 <tt>epmd.service</tt> and <tt>epmd.socket</tt> and requiring manual operator intervention to recover.</p><p>This issue affects OTP from OTP 17.0 before OTP&nbsp;29.0.4, OTP&nbsp;28.5.0.4 and OTP&nbsp;27.3.4.15.</p>"}],"value":"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.\n\nThe 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.\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 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15."}],"impacts":[{"capecId":"CAPEC-227","descriptions":[{"lang":"en","value":"CAPEC-227 Sustained Client Engagement"}]}],"metrics":[{"cvssV4_0":{"attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"NETWORK","baseScore":6.3,"baseSeverity":"MEDIUM","privilegesRequired":"NONE","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"LOW","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-755","description":"CWE-755 Improper Handling of Exceptional Conditions","lang":"en","type":"CWE"},{"cweId":"CWE-770","description":"CWE-770 Allocation of Resources Without Limits or Throttling","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-07-27T16:11:33.934Z","orgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","shortName":"EEF"},"references":[{"tags":["vendor-advisory","related"],"url":"https://github.com/erlang/otp/security/advisories/GHSA-h6f3-hx58-xhj6"},{"tags":["related"],"url":"https://cna.erlef.org/cves/CVE-2026-42792.html"},{"tags":["related"],"url":"https://osv.dev/vulnerability/EEF-CVE-2026-42792"},{"tags":["x_version-scheme"],"url":"https://www.erlang.org/doc/system/versions.html#order-of-versions"},{"tags":["patch"],"url":"https://github.com/erlang/otp/commit/865d203e4a6a8f44179eced9e1428f9259e4a3bb"}],"source":{"discovery":"EXTERNAL"},"title":"epmd permanent DoS via EMFILE on accept(2) in erts","workarounds":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<ul><li>Restrict epmd to loopback only by adding a systemd socket override: set <tt>ListenStream=</tt> (empty, to clear), then <tt>ListenStream=127.0.0.1:4369</tt> and <tt>ListenStream=[::1]:4369</tt> in <tt>/etc/systemd/system/epmd.socket.d/override.conf</tt>.</li><li>On systemd-managed systems, raise the file descriptor limit and configure automatic restart by adding <tt>LimitNOFILE=65536</tt> and <tt>Restart=always</tt> with a suitable <tt>RestartSec</tt> in <tt>/etc/systemd/system/epmd.service.d/override.conf</tt>.</li><li>Restrict network access to TCP port 4369 via firewall rules to trusted hosts only.</li></ul>"}],"value":"* Restrict epmd to loopback only by adding a systemd socket override: set ListenStream= (empty, to clear), then ListenStream=127.0.0.1:4369 and ListenStream=[::1]:4369 in /etc/systemd/system/epmd.socket.d/override.conf.\n* On systemd-managed systems, raise the file descriptor limit and configure automatic restart by adding LimitNOFILE=65536 and Restart=always with a suitable RestartSec in /etc/systemd/system/epmd.service.d/override.conf.\n* Restrict network access to TCP port 4369 via firewall rules to trusted hosts only."}],"x_generator":{"engine":"cvelib 1.8.0"}}},"cveMetadata":{"assignerOrgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","assignerShortName":"EEF","cveId":"CVE-2026-42792","datePublished":"2026-07-27T14:58:24.426Z","dateReserved":"2026-04-29T18:06:33.251Z","dateUpdated":"2026-07-27T16:11:33.934Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"}