Skip to main content
VulnerabilityPublished

CVE-2026-32689: Phoenix · Long-poll NDJSON body splitting causes large memory allocation

Affects phoenixSource GCVE Database

0
Authoritative record:CVE-2026-32689· High 8.7

Not known to be exploited · CVSS 8.7 High : upgrade to 1.7.22 soon.

Data as of 27 Oct 2026, 00:07 UTC

CVSS 4.0 base score
8.7High
How severe the flaw is on the 0–10 CVSS scale.
Patch
Available – fixed in 1.7.22, 1.8.6
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 5 May 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade phoenix to 1.7.22; phoenix to 1.8.6.

Affected software

ProductAffectedFixed in
HexphoenixAffected
  • >=1.7.0 <1.7.22
Fixed in
  • 1.7.22
HexphoenixAffected
  • >=1.8.0 <1.8.6
Fixed in
  • 1.8.6

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

### Summary An unauthenticated denial-of-service vulnerability in Phoenix's long-poll transport allows a remote client to allocate a large amount of memory with a HTTP request. A handful of concurrent requests can be sufficient to let the node run out of memory. See also https://cna.erlef.org/cves/CVE-2026-32689.html. ### Details The unoptimised code path exists on the `application/x-ndjson` POST handling in the LongPoll transport. The endpoint requires only a session token, which any client can obtain by issuing a GET to the same URL with a matching `Origin` header, so exploitation is unauthenticated. ### Impact Anyone who runs a LiveView app with a public Longpoll socket or uses a `Phoenix.Socket` with longpoll option. Longpoll has been enabled for newly generated Phoenix projects since Phoenix 1.7.11.

References

Community reviews

Loading reviews…