Vulnerability in MailPress (WordPress plugin) (CVE-2026-18436)
Summary
Vulnerability in MailPress (WordPress plugin) (CVE-2026-18436). Risk of unauthorized operations or information disclosure. Exploitable via POST /wp-json/mailpress/v1/campaign/.
Original description
The description as published by the source.
The MailPress plugin for WordPress is vulnerable to unauthorized access in versions up to, and including, 1.5.0 via the campaign revision-restore REST endpoint (POST /wp-json/mailpress/v1/campaign//restore-revision/). The route in the vulnerable range was registered without a permissionCallback, allowing the restoreRevision() handler to run for unauthenticated requests and overwrite a campaign's content_html with any prior revision. This makes it possible for unauthenticated attackers to modify campaign content by restoring an arbitrary revision.
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-2026-18436 has been found in MailPress (WordPress plugin).
Attackers can target a specific entry point like POST /wp-json/mailpress/v1/campaign/ over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "MailPress (WordPress plugin) CVE-2026-18436" on the vendor's site.
CVE-2026-18436 (MailPress (WordPress plugin)) — CWE-862 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: POST /wp-json/mailpress/v1/campaign/
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-862) exists in MailPress (WordPress plugin). Attackers reach the vulnerable code path via POST /wp-json/mailpress/v1/campaign/ without authentication.
Check the vendor advisory for the affected versions of MailPress (WordPress plugin). Attack surface: POST /wp-json/mailpress/v1/campaign/.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
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 /wp-json/mailpress/v1/campaign/ requests with malformed payloads or SQL meta-characters. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで MailPress (WordPress plugin) を使っているサービスとバージョンを洗い出す。
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2Hunt for indicators of compromise detect
grep 'POST /wp-json/mailpress/v1/campaign/' /var/log/nginx/access.log | grep -E '(unusual_payload|sqli_pattern)'アクセスログで
POST /wp-json/mailpress/v1/campaign/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。 -
3Post-deployment verification verify
Replay attack against POST /wp-json/mailpress/v1/campaign/ 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。
References
- web security@wordfence.com
- web security@wordfence.com
- web security@wordfence.com
- web nvd.nist.gov
- web github.com