GHSA-jfc2-q6qh-g5x8
Suggest an improvement- Source
- https://github.com/advisories/GHSA-jfc2-q6qh-g5x8
- Import Source
- https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-jfc2-q6qh-g5x8/GHSA-jfc2-q6qh-g5x8.json
- JSON Data
- https://api.osv.dev/v1/vulns/GHSA-jfc2-q6qh-g5x8
- Aliases
- Published
- 2026-05-13T21:32:06Z
- Modified
- 2026-05-19T20:26:06.334145132Z
- Severity
-
- 8.2 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
- Summary
- Cowboy: Unbounded buffer accumulation in multipart header parsing causes denial of service in cowboy
- Details
-
Allocation of Resources Without Limits or Throttling vulnerability in ninenines cowboy allows denial of service via unbounded buffer accumulation in multipart header parsing.
cowboyreq:readpart/3 in src/cowboyreq.erl accumulates incoming request bytes into a Buffer binary with no upper-bound check. When cowmultipart:parseheaders/2 returns more or {more, Buffer2}, the function reads up to Length bytes (default 64 KB) from the request body and recurses with the enlarged buffer. There is no equivalent of the bytesize(Acc) > Length guard present in the sibling function readpartbody/4. An unauthenticated attacker can send a multipart/form-data request whose body never yields a complete header section — for example, a body that never contains the advertised boundary delimiter, or one whose header lines never contain \r\n\r\n — and force the server process to accumulate memory linearly with the bytes the protocol layer is willing to deliver. A handful of concurrent such uploads is sufficient to exhaust BEAM memory.
This issue affects cowboy from 2.0.0 before 2.15.0.
- Database specific
{ "severity": "HIGH", "nvd_published_at": "2026-05-13T19:17:30Z", "github_reviewed": true, "cwe_ids": [ "CWE-770" ], "github_reviewed_at": "2026-05-19T20:12:33Z" }- References
Affected packages
Hex / cowboy
Package
- Name
- cowboy
- Purl
- pkg:hex/cowboy