punchin-email: Operator inbox (FORWARD_TO) disclosed to correspondents on reply — Cloudflare forward() drops the relay Reply-To (CVE-2026-54649) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-54649

punchin-email: Operator inbox (FORWARD_TO) disclosed to correspondents on reply — Cloudflare forward() drops the relay Reply-To

Answer in brief

CVE-2026-54649 records a Unknown severity vulnerability in punchin-email: Operator inbox (FORWARD_TO) disclosed to correspondents on reply — Cloudflare forward() drops the relay Reply-To. The current sources do not mark it as known exploited. The current feed maps PunchIn-App/punchin-email (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 17, 2026Updated Sep 17, 2026Source checked Sep 17, 2026First seen by HOL Sep 17, 2026Material review Sep 17, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps PunchIn-App/punchin-email (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
PunchIn-App/punchin-emailgeneric	< 1.5.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for PunchIn-App/punchin-email.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 17, 2026

Sources and claim methodology

Upstream source description

punchin-email is a Cloudflare Email Worker that provides two-way role aliases while relaying mail to a private inbox. Prior to 1.5.0, handleInbound delivers inbound alias mail with message.forward(), which silently drops the added Reply-To header intended to route responses through the relay. When a correspondent sends mail to an alias and the operator replies, the mail client can send directly to the correspondent from the private FORWARD_TO inbox address, exposing that address. The disclosure is limited to the operator's own email address and does not expose third-party data or provide code execution or authentication bypass. This issue is fixed in version 1.5.0.

Quoted source text, attributed separately from HOL analysis.