# cowboy (Hex) vulnerabilities

4 known vulnerabilities (2 high, 2 medium), with the versions each affects and the releases that fix them.

## At a glance

- Latest release: not known (cve.now hasn't read this package's releases)
- Newest unaffected release: not known without release data
- Registry: https://hex.pm/packages/cowboy

## Advisories (4)

### [CVE-2026-115701](https://cve.now/CVE-2026-115701): Cowboy HTTP/1.1 Unbounded Buffering of Pipelined Data During Request Handling Enables Memory Exhaustion

- Severity: High 8.2
- Published: Nov 6, 2026
- Affected: from 2.18.0; from 2.18.0.

### [CVE-2026-65624](https://cve.now/CVE-2026-65624): Cowboy HTTP/1.1 max\_headers Bypass via Duplicate Header Names Enables Memory Exhaustion

- Severity: Medium 6.9
- Published: Jul 28, 2026
- Affected: from 2.0.0-pre.4, fixed in 2.18.0; from 2.0.0-pre.4, fixed in 2.18.0.

### [CVE-2026-43966](https://cve.now/CVE-2026-43966): HTTP Response Splitting via Non-VCHAR Bytes in cow\_http\_struct\_hd:escape\_string/2

- Severity: Medium 6.3
- Published: Jun 8, 2026
- Affected: fixed in 2.16.0.

### [CVE-2026-8466](https://cve.now/CVE-2026-8466): Unbounded buffer accumulation in multipart header parsing causes denial of service in cowboy

- Severity: High 8.2
- Published: May 13, 2026
- Affected: from 2.0.0, fixed in 2.15.0; from 2.0.0, fixed in 2.15.0.

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