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TI-2026-25333 Aliases CVE-2026-32873GHSA-4w98-xf39-23gp

ewe: Loop with Unreachable Exit Condition ('Infinite Loop')

Priority HIGH 72CWE-825Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-835.

Summary

ewe is a Gleam web server. Versions 0.8.0 through 3.0.4 contain a bug in the handle_trailers function where rejected trailer headers (forbidden or undeclared) cause an infinite loop. When handle_trailers encounters such a trailer, three code paths (lines 520, 523, 526) recurse with the original buffer (rest) instead of advancing past the rejected header (Buffer(header_rest, 0)), causing decoder.decode_packet to re-parse the same header on every iteration. The resulting loop has no timeout or escape — the BEAM process permanently wedges at 100% CPU. Any application that calls ewe.read_body on chunked requests is affected, and this is exploitable by any unauthenticated remote client before control returns to application code, making an application-level workaround impossible. This issue is fixed in version 3.0.5.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00623 50th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed ewe (vshakitskiy): 3.0.5ewe (Hex): 3.0.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
vshakitskiyewe0.8.0 to before 3.0.53.0.5Patch availableCNA
—ewe (Hex)0.8.0 to before 3.0.53.0.5Patch availableGHSA-4w98-xf39-23gp
  • ewe Vendorvshakitskiy Affected 0.8.0 to before 3.0.5 Fixed in 3.0.5 Patch available CNA
  • ewe (Hex) Vendor— Affected 0.8.0 to before 3.0.5 Fixed in 3.0.5 Patch available GHSA-4w98-xf39-23gp

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:vshakitskiy:ewe:*:*:*:*:*:*:*:*0.8.0 to before 3.0.5Vulnerablevshakitskiy
  • cpe:2.3:a:vshakitskiy:ewe:*:*:*:*:*:*:*:* Versions 0.8.0 to before 3.0.5 Vulnerable ·vshakitskiy

Remediation

  • Fix · CNA ewe (vshakitskiy) Fixed in 3.0.5
  • Fix · GHSA-4w98-xf39-23gp ewe (Hex) Fixed in 3.0.5 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-32873
  2. 2026-10-03 Alias added: GHSA-4w98-xf39-23gp
  3. 2026-10-18 EPSS moved to the 50th–90th percentile
  4. 2026-10-25 EPSS moved to the below the 50th percentile
  5. 2026-11-06 EPSS moved to the 50th–90th percentile

References

Exploit 1

Patch 2

Advisory 1

Other 1

  • TI-2026-26959 ewe Has Improper Neutralization of CRLF Sequences in HTTP Headers (HTTP Request/Response Splitting) CVSS 3.1MEDIUM 5.3
  • TI-2026-25340 ewe has an Overly Permissive List of Allowed Inputs CVSS 3.1MEDIUM 5.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences