Vulnerability in @agenticmail/core (CVE-2026-57495)
Summary
Vulnerability in @agenticmail/core (CVE-2026-57495). Risk of unauthorized operations or information disclosure. Exploitable via POST /mail/inbound. Mitigation: upgrade to 0.9.43 or later.
Original description
The description as published by the source.
Summary
Two inbound-mail handlers act on a privileged effect without verifying that the sender is the operator, while a sibling handler in the same repo does. The higher-impact one: any external email routed to the bridge inbox causes the dispatcher to resume the operator's Claude Code session with permissionMode: 'bypassPermissions', embedding the attacker-controlled from/subject/preview verbatim into the prompt the resumed agent reads — an indirect prompt injection into a fully-privileged agent (Bash/Write/Edit/WebFetch + the agenticmail MCP toolbelt) running as the operator's OAuth identity. The sibling operator-query email-reply hook gates the same untrusted-From provenance with isOperatorReplySender(replyFrom, config.operatorEmail) (fail-closed); the bridge-wake path — a strictly higher-privilege effect — has no equivalent.
Affected code (current HEAD, commit b95f52e)
Untrusted provenance: external inbound email enters at packages/api/src/routes/inbound.ts:41 (POST /mail/inbound); the x-inbound-secret authenticates only the relay->API hop, not the external sender, so from/subject/preview are attacker-controlled.
Privileged sink (bridge-wake, bypassPermissions):
packages/claudecode/src/dispatcher.ts:2040handleBridgeMailextractssubject/from/preview(:2045-2049) and callsplanBridgeWake({ session, mail: { ..., from, preview } })(:2052) with NO sender check — routing keys only on session freshness (skip-live / escalate / resu…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-57495 has been found in @agenticmail/core.
Attackers can target a specific entry point like POST /mail/inbound over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade @agenticmail/core to 0.9.43 or later.
If unsure, ask your IT team or search "@agenticmail/core CVE-2026-57495" on the vendor's site.
CVE-2026-57495 (@agenticmail/core) — CWE-306
Attack surface: POST /mail/inbound / from / subject / preview
Patched: 0.9.43 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-306) exists in @agenticmail/core. Attackers reach the vulnerable code path via POST /mail/inbound.
Check the vendor advisory for the affected versions of @agenticmail/core. Attack surface: POST /mail/inbound / from / subject / preview.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 0.9.43.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual POST /mail/inbound requests with malformed payloads or SQL meta-characters. Run grep -r '@agenticmail/core' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r '@agenticmail/core' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
@agenticmail/coreを grep し、稼働しているサービス・バージョンを把握する。 -
2Hunt for indicators of compromise detect
grep 'POST /mail/inbound' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /mail/inboundへの異常なリクエスト (不正な認証ヘッダ・SQLメタ文字)を過去 30〜90日分捜索。WAF/SIEM があれば該当パスのアラート発火履歴を確認。 -
3Apply patch patch
Upgrade @agenticmail/core to 0.9.43ステージング環境で 0.9.43 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 2 で見つけた異常検知の続報チェックを含めること。
-
4Post-deployment verification verify
Replay attack against POST /mail/inbound on staging to confirm patch closes the vectorパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 2 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com