GHSA-628h-q48j-jr6q

Source

https://github.com/advisories/GHSA-628h-q48j-jr6q

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-628h-q48j-jr6q/GHSA-628h-q48j-jr6q.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-628h-q48j-jr6q

Aliases

Published

2026-05-08T20:24:15Z

Modified

2026-05-08T20:31:38Z

Severity

8.7 (High) CVSS_V4 - 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 CVSS Calculator

Summary

Phoenix: Long-poll NDJSON body splitting causes large memory allocation

Details

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.

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.

Database specific

{
    "cwe_ids":  [
        "CWE-770"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-05-08T20:24:15Z",
    "nvd_published_at":  "2026-05-05T16:16:11Z",
    "severity":  "HIGH"
}

References

Affected packages

Hex / phoenix

Package

Name: phoenix
Purl: pkg:hex/phoenix

Affected ranges

Type: SEMVER
Events: Introduced

1.7.0

Fixed

1.7.22

Affected versions

1.*

1.7.0

1.7.1

1.7.2

1.7.3

1.7.4

1.7.5

1.7.6

1.7.7

1.7.8

1.7.9

1.7.10

1.7.11

1.7.12

1.7.13

1.7.14

1.7.15

1.7.16

1.7.17

1.7.18

1.7.19

1.7.20

1.7.21

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-628h-q48j-jr6q/GHSA-628h-q48j-jr6q.json"

Hex / phoenix

Package

Name: phoenix
Purl: pkg:hex/phoenix

Affected ranges

Type: SEMVER
Events: Introduced

1.8.0

Fixed

1.8.6

Affected versions

1.*

1.8.0

1.8.1

1.8.2

1.8.3

1.8.4

1.8.5

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-628h-q48j-jr6q/GHSA-628h-q48j-jr6q.json"