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TI-2023-06068 Aliases CVE-2023-6621GHSA-gr9g-7x3w-8vjj

Post SMTP < 2.8.7 - Reflected Cross-Site Scripting

Priority MEDIUM 60CWE-79Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-79.

Summary

The POST SMTP WordPress plugin before 2.8.7 does not sanitise and escape the msg parameter before outputting it back in the page, leading to a Reflected Cross-Site Scripting which could be used against high privilege users such as admin.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00401 34th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA and NVD
Fix Fixed POST SMTP (Unknown): 2.8.7

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
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
UnknownPOST SMTPbefore 2.8.72.8.7Patch availableCNA
  • POST SMTP VendorUnknown Affected before 2.8.7 Fixed in 2.8.7 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:wpexperts:post_smtp:*:*:*:*:*:wordpress:*:*before 2.8.7VulnerableWPExperts
  • cpe:2.3:a:wpexperts:post_smtp:*:*:*:*:*:wordpress:*:* Versions before 2.8.7 Vulnerable ·WPExperts

Remediation

  • Fix · CNA POST SMTP (Unknown) Fixed in 2.8.7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-6621
  2. 2026-10-03 Alias added: GHSA-gr9g-7x3w-8vjj

References

Exploit 1

  • TI-2023-06280 Authorization bypass in saadiqbal Post SMTP – Complete Email Deliverability and SMTP… CVSS 3.1CRITICAL 9.8
  • TI-2023-02978 POST SMTP Mailer < 2.5.7 - Account Takeover via CSRF CVSS 3.1HIGH 8.8
  • TI-2023-06067 Post SMTP < 2.8.7 - Admin+ SQL Injection CVSS 3.1HIGH 7.2
  • TI-2022-02171 Post SMTP < 2.1.7 - Admin+ Blind SSRF CVSS 3.1HIGH 7.2
  • TI-2023-02977 POST SMTP Mailer < 2.5.7 - Arbitrary Log Deletion via CSRF CVSS 3.1MEDIUM 4.3
  • TI-2023-28661 WordPress POST SMTP Mailer plugin <= 2.8.6 - Broken Access Control on API vulnerability CVSS 3.1CRITICAL 9.8
See all 18 →

Sources

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