CVE-2026-32881 | ewe has an Overly Permissive List of Allowed Inputs

Exp

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.

Published: 2026-03-20 Last update: 2026-03-23 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-32881 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2026-32881

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-32881

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-21 0.16% 0.06% -0.09%
2 2026-03-24 0.07% 0.16% +0.09%
3 2026-03-20 0.07%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-32881

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 1.4 [email protected]

Weakness enumeration for CVE-2026-32881

GitHub Security Advisory for CVE-2026-32881

GHSA-9w88-79f8-m3vp · Severity: medium · Ecosystem: erlang — Permissive List of Allowed Inputs in ewe

Affected software / configurations for CVE-2026-32881

Vendor Product Version Raw CPE
vshakitskiy ewe < 3.0.5 cpe:2.3:a:vshakitskiy:ewe:*:*:*:*:*:*:*:*

References for CVE-2026-32881

cvelogic Threat Intelligence