Vulnerability in Joomla Joomla\!

CVE-2016-10033

The mailSend function in the isMail transport in PHPMailer before 5.2.18 might allow remote attackers to pass extra parameters to the mail command and consequently execute arbitrary code via a \" (backslash double quote) in a crafted Sende…

EPSS: 0.997 (100.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Public proof-of-concept exploits

References

  • cve@mitre.org (Exploit, VDB Entry, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (x_refsource_CONFIRM, Third Party Advisory)
  • cve@mitre.org (Exploit, VDB Entry, Third Party Advisory, exploit, x_refsource_EXPLOIT-DB)
  • cve@mitre.org (Exploit, VDB Entry, Third Party Advisory, exploit, x_refsource_EXPLOIT-DB)
  • cve@mitre.org (Exploit, VDB Entry, Third Party Advisory, exploit, x_refsource_EXPLOIT-DB)
  • cve@mitre.org (Exploit, Patch, VDB Entry, Third Party Advisory, exploit, x_refsource_EXPLOIT-DB)
  • cve@mitre.org (Exploit, Patch, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (x_refsource_CONFIRM, Patch, Vendor Advisory)
  • cve@mitre.org (mailing-list, x_refsource_BUGTRAQ, VDB Entry, Third Party Advisory, Broken Link)
  • cve@mitre.org (x_refsource_CONFIRM, Patch, Vendor Advisory)

Frequently asked questions

What is CVE-2016-10033?
CVE-2016-10033 is a critical-severity vulnerability in Joomla Joomla\!, classified under Argument Injection. CVSS score: 9.8/10. Published 2016-12-30.
How severe is CVE-2016-10033?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2016-10033 known to be exploited?
Yes. CVE-2016-10033 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-07-07), indicating it is being actively exploited. 226 public proof-of-concept repositories are indexed.