Phoenix JavaScript presence client crashes on presence keys colliding with Object.prototype members in Presence.syncState/syncDiff
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 1.5.15, 1.6.17, 1.7.24, 1.8.9
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: poc
- Automatable: no
- Technical impact: partial
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; 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.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: poc · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- phoenix
From 1.2.0-rc.0 · fixed in 1.5.15; From 1.6.0-rc.0 · fixed in 1.6.17; From 1.7.0-rc.0 · fixed in 1.7.24; From 1.8.0-rc.0 · fixed in 1.8.9
- phoenixframework/phoenix
From 2270aaf21bd02c6a6a1022820564efb605a97655 · fixed in *
- phoenixHex
From 1.2.0-rc.0 · fixed in 1.5.15; From 1.6.0-rc.0 · fixed in 1.6.17; From 1.7.0-rc.0 · fixed in 1.7.24; From 1.8.0-rc.0 · fixed in 1.8.9
- phoenixnpm
From 1.2.0-rc.0 · fixed in 1.5.15; From 1.6.0-rc.0 · fixed in 1.6.17; From 1.7.0-rc.0 · fixed in 1.7.24; From 1.8.0-rc.0 · fixed in 1.8.9
- phoenixHex
From 1.2.0-rc.0 · fixed in 1.5.15
- phoenixHex
From 1.6.0-rc.0 · fixed in 1.6.17
- phoenixHex
From 1.7.0-rc.0 · fixed in 1.7.24
- phoenixHex
From 1.8.0-rc.0 · fixed in 1.8.9
- phoenixnpm
From 1.2.0-rc.0 · fixed in 1.5.15
- phoenixnpm
From 1.6.0-rc.0 · fixed in 1.6.17
- phoenixnpm
From 1.7.0-rc.0 · fixed in 1.7.24
- phoenixnpm
From 1.8.0-rc.0 · fixed in 1.8.9