CVE-2026-56812 (GCVE-0-2026-56812)
Vulnerability from cvelistv5 – Published: 2026-07-07 15:22 – Updated: 2026-07-07 16:11
VLAI
Title
Phoenix JavaScript presence client crashes on presence keys colliding with Object.prototype members in Presence.syncState/syncDiff
Summary
Improper Check for Unusual or Exceptional Conditions vulnerability in phoenixframework phoenix (Presence JavaScript client) allows an attacker with ordinary channel access to cause a persistent client-side denial of service against every viewer of a presence channel topic.
This vulnerability is associated with program files assets/js/phoenix/presence.js and program routines Presence.syncState and Presence.syncDiff.
The Phoenix JavaScript presence client checks whether a presence already exists with a bare truthiness test (state[key]) instead of an own-property check. Presence keys can be attacker-controlled, because applications track presences under a username or id supplied by the client. A user who joins a channel choosing a key that is an Object.prototype member name (__proto__, constructor, toString, hasOwnProperty, and similar) makes that lookup return JavaScript's built-in Object.prototype instead of undefined. Because the prototype is truthy, the code treats it as an existing presence and reads .metas.map(...) off it, which throws an uncaught TypeError.
The exception propagates out of the presence message handler, so the local state is never updated and onSync() never fires. Because the malicious key is tracked on the server, it is re-pushed on every presence update and keeps re-throwing, so presence sync stays broken for every viewer of that channel topic until the attacker leaves. Both syncState and syncDiff use the same unsafe existence-check pattern. The impact is limited to the affected topic and is a read-time confusion of the prototype object, not a mutation of Object.prototype (it is not prototype pollution).
This issue affects phoenix: from 1.2.0-rc.0 before 1.5.15, from 1.6.0-rc.0 before 1.6.17, from 1.7.0-rc.0 before 1.7.24, and from 1.8.0-rc.0 before 1.8.9.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
References
7 references
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| phoenixframework | phoenix |
Affected:
1.2.0-rc.0 , < 1.5.15
(semver)
Affected: 1.6.0-rc.0 , < 1.6.17 (semver) Affected: 1.7.0-rc.0 , < 1.7.24 (semver) Affected: 1.8.0-rc.0 , < 1.8.9 (semver) cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:* |
|
| phoenixframework | phoenix |
Affected:
2270aaf21bd02c6a6a1022820564efb605a97655 , < *
(git)
cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:* |
Credits
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Presence keys can be attacker-controlled, because applications track presences under a username or id supplied by the client. A user who joins a channel choosing a key that is an Object.prototype member name (__proto__, constructor, toString, hasOwnProperty, and similar) makes that lookup return JavaScript\u0027s built-in Object.prototype instead of undefined. Because the prototype is truthy, the code treats it as an existing presence and reads .metas.map(...) off it, which throws an uncaught TypeError.\\n\\nThe exception propagates out of the presence message handler, so the local state is never updated and onSync() never fires. Because the malicious key is tracked on the server, it is re-pushed on every presence update and keeps re-throwing, so presence sync stays broken for every viewer of that channel topic until the attacker leaves. Both syncState and syncDiff use the same unsafe existence-check pattern. The impact is limited to the affected topic and is a read-time confusion of the prototype object, not a mutation of Object.prototype (it is not prototype pollution).\\n\\nThis issue affects phoenix: from 1.2.0-rc.0 before 1.5.15, from 1.6.0-rc.0 before 1.6.17, from 1.7.0-rc.0 before 1.7.24, and from 1.8.0-rc.0 before 1.8.9.\"}],\"affected\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"affectedData\":[{\"vendor\":\"phoenixframework\",\"product\":\"phoenix\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://repo.hex.pm\",\"packageName\":\"phoenix\",\"cpes\":[\"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\"],\"modules\":[\"Presence\"],\"programFiles\":[\"assets/js/phoenix/presence.js\"],\"programRoutines\":[{\"name\":\"Presence.syncState\"},{\"name\":\"Presence.syncDiff\"}],\"repo\":\"https://github.com/phoenixframework/phoenix\",\"packageURL\":\"pkg:hex/phoenix\",\"versions\":[{\"version\":\"1.2.0-rc.0\",\"lessThan\":\"1.5.15\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"1.6.0-rc.0\",\"lessThan\":\"1.6.17\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"1.7.0-rc.0\",\"lessThan\":\"1.7.24\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"1.8.0-rc.0\",\"lessThan\":\"1.8.9\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"phoenixframework\",\"product\":\"phoenix\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://registry.npmjs.org\",\"packageName\":\"phoenix\",\"cpes\":[\"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\"],\"modules\":[\"Presence\"],\"programFiles\":[\"assets/js/phoenix/presence.js\"],\"programRoutines\":[{\"name\":\"Presence.syncState\"},{\"name\":\"Presence.syncDiff\"}],\"repo\":\"https://github.com/phoenixframework/phoenix\",\"packageURL\":\"pkg:npm/phoenix\",\"versions\":[{\"version\":\"1.2.0-rc.0\",\"lessThan\":\"1.5.15\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"1.6.0-rc.0\",\"lessThan\":\"1.6.17\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"1.7.0-rc.0\",\"lessThan\":\"1.7.24\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"1.8.0-rc.0\",\"lessThan\":\"1.8.9\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"phoenixframework\",\"product\":\"phoenix\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://github.com\",\"packageName\":\"phoenixframework/phoenix\",\"cpes\":[\"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\"],\"modules\":[\"Presence\"],\"programFiles\":[\"assets/js/phoenix/presence.js\"],\"programRoutines\":[{\"name\":\"Presence.syncState\"},{\"name\":\"Presence.syncDiff\"}],\"repo\":\"https://github.com/phoenixframework/phoenix\",\"packageURL\":\"pkg:github/phoenixframework/phoenix\",\"versions\":[{\"version\":\"2270aaf21bd02c6a6a1022820564efb605a97655\",\"lessThan\":\"*\",\"versionType\":\"git\",\"status\":\"affected\",\"changes\":[{\"at\":\"7f7b971c1ea0994e3fbd1c11ddb05e780bd38ad8\",\"status\":\"unaffected\"},{\"at\":\"89a1c4be161e436241e12b2378a719904b9bd96f\",\"status\":\"unaffected\"},{\"at\":\"b90b22521465ece00eb5a19d5aa2b9465b209c85\",\"status\":\"unaffected\"},{\"at\":\"beffc4da1e787e572121f68902c63daf4fe7d9c2\",\"status\":\"unaffected\"}]}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":6.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"LOW\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-07-07T16:11:03.353715Z\",\"id\":\"CVE-2026-56812\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA 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"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-56812\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-07T16:11:03.353715Z\"}}}], \"references\": [{\"url\": \"https://github.com/phoenixframework/phoenix/security/advisories/GHSA-63mc-hw7g-86rr\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-07T16:10:49.072Z\"}}], \"cna\": {\"title\": \"Phoenix JavaScript presence client crashes on presence keys colliding with Object.prototype members in Presence.syncState/syncDiff\", \"source\": {\"discovery\": \"EXTERNAL\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"Peter Ullrich\"}, {\"lang\": \"en\", \"type\": \"analyst\", \"value\": \"Jonatan M\\u00e4nnchen\"}, {\"lang\": \"en\", \"type\": \"analyst\", \"value\": \"Jos\\u00e9 Valim\"}, {\"lang\": \"en\", \"type\": \"remediation developer\", \"value\": \"Steffen Deusch\"}], \"impacts\": [{\"capecId\": \"CAPEC-153\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"CAPEC-153 Input Data Manipulation\"}]}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 6.3, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"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\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"LOW\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"cpes\": [\"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/phoenixframework/phoenix\", \"vendor\": \"phoenixframework\", \"modules\": [\"Presence\"], \"product\": \"phoenix\", \"versions\": [{\"status\": \"affected\", \"version\": \"1.2.0-rc.0\", \"lessThan\": \"1.5.15\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"1.6.0-rc.0\", \"lessThan\": \"1.6.17\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"1.7.0-rc.0\", \"lessThan\": \"1.7.24\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"1.8.0-rc.0\", \"lessThan\": \"1.8.9\", \"versionType\": \"semver\"}], \"packageURL\": \"pkg:hex/phoenix\", \"packageName\": \"phoenix\", \"programFiles\": [\"assets/js/phoenix/presence.js\"], \"collectionURL\": \"https://repo.hex.pm\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"Presence.syncState\"}, {\"name\": \"Presence.syncDiff\"}]}, {\"cpes\": [\"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/phoenixframework/phoenix\", \"vendor\": \"phoenixframework\", \"modules\": [\"Presence\"], \"product\": \"phoenix\", \"versions\": [{\"status\": \"affected\", \"version\": \"1.2.0-rc.0\", \"lessThan\": \"1.5.15\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"1.6.0-rc.0\", \"lessThan\": \"1.6.17\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"1.7.0-rc.0\", \"lessThan\": \"1.7.24\", \"versionType\": \"semver\"}, {\"status\": \"affected\", \"version\": \"1.8.0-rc.0\", \"lessThan\": \"1.8.9\", \"versionType\": \"semver\"}], \"packageURL\": \"pkg:npm/phoenix\", \"packageName\": \"phoenix\", \"programFiles\": [\"assets/js/phoenix/presence.js\"], \"collectionURL\": \"https://registry.npmjs.org\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"Presence.syncState\"}, {\"name\": \"Presence.syncDiff\"}]}, {\"cpes\": [\"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/phoenixframework/phoenix\", \"vendor\": \"phoenixframework\", \"modules\": [\"Presence\"], \"product\": \"phoenix\", \"versions\": [{\"status\": \"affected\", \"changes\": [{\"at\": \"7f7b971c1ea0994e3fbd1c11ddb05e780bd38ad8\", \"status\": \"unaffected\"}, {\"at\": \"89a1c4be161e436241e12b2378a719904b9bd96f\", \"status\": \"unaffected\"}, {\"at\": \"b90b22521465ece00eb5a19d5aa2b9465b209c85\", \"status\": \"unaffected\"}, {\"at\": \"beffc4da1e787e572121f68902c63daf4fe7d9c2\", \"status\": \"unaffected\"}], \"version\": \"2270aaf21bd02c6a6a1022820564efb605a97655\", \"lessThan\": \"*\", \"versionType\": \"git\"}], \"packageURL\": \"pkg:github/phoenixframework/phoenix\", \"packageName\": \"phoenixframework/phoenix\", \"programFiles\": [\"assets/js/phoenix/presence.js\"], \"collectionURL\": \"https://github.com\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"Presence.syncState\"}, {\"name\": \"Presence.syncDiff\"}]}], \"references\": [{\"url\": \"https://github.com/phoenixframework/phoenix/security/advisories/GHSA-63mc-hw7g-86rr\", \"tags\": [\"vendor-advisory\", \"related\"]}, {\"url\": \"https://cna.erlef.org/cves/CVE-2026-56812.html\", \"tags\": [\"related\"]}, {\"url\": \"https://osv.dev/vulnerability/EEF-CVE-2026-56812\", \"tags\": [\"related\"]}, {\"url\": \"https://github.com/phoenixframework/phoenix/commit/7f7b971c1ea0994e3fbd1c11ddb05e780bd38ad8\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/phoenixframework/phoenix/commit/89a1c4be161e436241e12b2378a719904b9bd96f\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/phoenixframework/phoenix/commit/b90b22521465ece00eb5a19d5aa2b9465b209c85\", \"tags\": [\"patch\"]}, {\"url\": \"https://github.com/phoenixframework/phoenix/commit/beffc4da1e787e572121f68902c63daf4fe7d9c2\", \"tags\": [\"patch\"]}], \"workarounds\": [{\"lang\": \"en\", \"value\": \"Reject or sanitize presence keys that collide with JavaScript Object.prototype member names (for example __proto__, constructor, prototype, toString, hasOwnProperty) before calling Phoenix.Presence.track, or namespace every presence key with a fixed prefix so that no key can equal a prototype member name. Alternatively, derive presence keys from server-controlled, validated values instead of raw user input.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eReject or sanitize presence keys that collide with JavaScript \u003ctt\u003eObject.prototype\u003c/tt\u003e member names (for example \u003ctt\u003e__proto__\u003c/tt\u003e, \u003ctt\u003econstructor\u003c/tt\u003e, \u003ctt\u003eprototype\u003c/tt\u003e, \u003ctt\u003etoString\u003c/tt\u003e, \u003ctt\u003ehasOwnProperty\u003c/tt\u003e) before calling \u003ctt\u003ePhoenix.Presence.track\u003c/tt\u003e, or namespace every presence key with a fixed prefix so that no key can equal a prototype member name. Alternatively, derive presence keys from server-controlled, validated values instead of raw user input.\u003c/p\u003e\", \"base64\": false}]}], \"x_generator\": {\"engine\": \"cvelib 1.8.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"Improper Check for Unusual or Exceptional Conditions vulnerability in phoenixframework phoenix (Presence JavaScript client) allows an attacker with ordinary channel access to cause a persistent client-side denial of service against every viewer of a presence channel topic.\\n\\nThis vulnerability is associated with program files assets/js/phoenix/presence.js and program routines Presence.syncState and Presence.syncDiff.\\n\\nThe Phoenix JavaScript presence client checks whether a presence already exists with a bare truthiness test (state[key]) instead of an own-property check. Presence keys can be attacker-controlled, because applications track presences under a username or id supplied by the client. A user who joins a channel choosing a key that is an Object.prototype member name (__proto__, constructor, toString, hasOwnProperty, and similar) makes that lookup return JavaScript\u0027s built-in Object.prototype instead of undefined. Because the prototype is truthy, the code treats it as an existing presence and reads .metas.map(...) off it, which throws an uncaught TypeError.\\n\\nThe exception propagates out of the presence message handler, so the local state is never updated and onSync() never fires. Because the malicious key is tracked on the server, it is re-pushed on every presence update and keeps re-throwing, so presence sync stays broken for every viewer of that channel topic until the attacker leaves. Both syncState and syncDiff use the same unsafe existence-check pattern. The impact is limited to the affected topic and is a read-time confusion of the prototype object, not a mutation of Object.prototype (it is not prototype pollution).\\n\\nThis issue affects phoenix: from 1.2.0-rc.0 before 1.5.15, from 1.6.0-rc.0 before 1.6.17, from 1.7.0-rc.0 before 1.7.24, and from 1.8.0-rc.0 before 1.8.9.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eImproper Check for Unusual or Exceptional Conditions vulnerability in phoenixframework phoenix (Presence JavaScript client) allows an attacker with ordinary channel access to cause a persistent client-side denial of service against every viewer of a presence channel topic.\u003c/p\u003e\u003cp\u003eThis vulnerability is associated with program files \u003ctt\u003eassets/js/phoenix/presence.js\u003c/tt\u003e and program routines \u003ctt\u003ePresence.syncState\u003c/tt\u003e and \u003ctt\u003ePresence.syncDiff\u003c/tt\u003e.\u003c/p\u003e\u003cp\u003eThe Phoenix JavaScript presence client checks whether a presence already exists with a bare truthiness test (\u003ctt\u003estate[key]\u003c/tt\u003e) instead of an own-property check. Presence keys can be attacker-controlled, because applications track presences under a username or id supplied by the client. A user who joins a channel choosing a key that is an \u003ctt\u003eObject.prototype\u003c/tt\u003e member name (\u003ctt\u003e__proto__\u003c/tt\u003e, \u003ctt\u003econstructor\u003c/tt\u003e, \u003ctt\u003etoString\u003c/tt\u003e, \u003ctt\u003ehasOwnProperty\u003c/tt\u003e, and similar) makes that lookup return JavaScript\u0027s built-in \u003ctt\u003eObject.prototype\u003c/tt\u003e instead of \u003ctt\u003eundefined\u003c/tt\u003e. Because the prototype is truthy, the code treats it as an existing presence and reads \u003ctt\u003e.metas.map(...)\u003c/tt\u003e off it, which throws an uncaught \u003ctt\u003eTypeError\u003c/tt\u003e.\u003c/p\u003e\u003cp\u003eThe exception propagates out of the presence message handler, so the local state is never updated and \u003ctt\u003eonSync()\u003c/tt\u003e never fires. Because the malicious key is tracked on the server, it is re-pushed on every presence update and keeps re-throwing, so presence sync stays broken for every viewer of that channel topic until the attacker leaves. Both \u003ctt\u003esyncState\u003c/tt\u003e and \u003ctt\u003esyncDiff\u003c/tt\u003e use the same unsafe existence-check pattern. The impact is limited to the affected topic and is a read-time confusion of the prototype object, not a mutation of \u003ctt\u003eObject.prototype\u003c/tt\u003e (it is not prototype pollution).\u003c/p\u003e\u003cp\u003eThis issue affects phoenix: from 1.2.0-rc.0 before 1.5.15, from 1.6.0-rc.0 before 1.6.17, from 1.7.0-rc.0 before 1.7.24, and from 1.8.0-rc.0 before 1.8.9.\u003c/p\u003e\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-754\", \"description\": \"CWE-754 Improper Check for Unusual or Exceptional Conditions\"}]}], \"configurations\": [{\"lang\": \"en\", \"value\": \"The application must use Phoenix.Presence (or otherwise drive the Phoenix JavaScript presence client) and track presences under keys that are influenced by untrusted client input, for example a username or id chosen by the connecting user. Applications that derive presence keys exclusively from server-controlled, validated values are not affected.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eThe application must use \u003ctt\u003ePhoenix.Presence\u003c/tt\u003e (or otherwise drive the Phoenix JavaScript presence client) and track presences under keys that are influenced by untrusted client input, for example a username or id chosen by the connecting user. Applications that derive presence keys exclusively from server-controlled, validated values are not affected.\u003c/p\u003e\", \"base64\": false}]}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"1.5.15\", \"versionStartIncluding\": \"1.2.0-rc.0\"}, {\"criteria\": \"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"1.6.17\", \"versionStartIncluding\": \"1.6.0-rc.0\"}, {\"criteria\": \"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"1.7.24\", \"versionStartIncluding\": \"1.7.0-rc.0\"}, {\"criteria\": \"cpe:2.3:a:phoenixframework:phoenix:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"1.8.9\", \"versionStartIncluding\": \"1.8.0-rc.0\"}], \"operator\": \"OR\"}], \"operator\": \"AND\"}], \"providerMetadata\": {\"orgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"shortName\": \"EEF\", \"dateUpdated\": \"2026-07-07T16:11:22.228Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-56812\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-07-07T16:11:22.228Z\", \"dateReserved\": \"2026-06-23T12:29:02.507Z\", \"assignerOrgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"datePublished\": \"2026-07-07T15:22:46.933Z\", \"assignerShortName\": \"EEF\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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