CVE-2026-32881

low-risk
Published 2026-03-20

ewe is a Gleam web server. ewe is a Gleam web server. Versions 0.6.0 through 3.0.4 are vulnerable to authentication bypass or spoofed proxy-trust headers. Chunked transfer encoding trailer handling merges declared trailer fields into req.headers after body parsing, but the denylist only blocks 9 header names. A malicious client can exploit this by declaring these headers in the Trailer field and appending them after the final chunk, causing request.set_header to overwrite legitimate values (e.g., those set by a reverse proxy). This enables attackers to forge authentication credentials, hijack sessions, bypass IP-based rate limiting, or spoof proxy-trust headers in any downstream middleware that reads headers after ewe.read_body is called. This issue has been fixed in version 3.0.5.

Do I need to act?

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0.19% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
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Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.3/10 Medium
NETWORK / LOW complexity

Affected Products (1)

Ewe

Affected Vendors

27
/ 100
low-risk
Severity 21/34 · High
Exploitability 1/34 · Minimal
Exposure 5/34 · Minimal