PatchTheCVECVE-2016-10074: The mail transport (aka Swift_Transport_MailTransport) in Swift Mailer before 5.4.5 might allow remote attacke
CVE-2016-10074 is a critical-severity flaw (CVSS 9.8) affecting swiftmailer. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
The mail transport (aka Swift_Transport_MailTransport) in Swift Mailer before 5.4.5 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 e-mail address in the (1) From, (2) ReturnPath, or (3) Sender header.
Why this priority
- Critical severity
- EPSS top 1%: very likely to be exploited
- Public exploit reference
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 43.8% (top 1%) |
| CISA exploited list | No |
| Weakness | CWE-77 |
| Published | 2016-12-30 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- Exploit-DB: PHPMailer < 5.2.20 / SwiftMailer < 5.4.5-DEV / Zend Framework / zend-mail < 2.4.11 - 'AIO' 'PwnScriptum' Remote Code Exe
- Exploit-DB: PHPMailer < 5.2.20 with Exim MTA - Remote Code Execution
- Exploit-DB: SwiftMailer < 5.4.5-DEV - Remote Code Execution
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2016-10074?
swiftmailer: upgrade to newer than 5.4.4. Exact commands for each OS are on this page.
Is CVE-2016-10074 being exploited?
CVE-2016-10074 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2016-10074 affect?
CVE-2016-10074 affects swiftmailer. Severity is critical (CVSS 9.8). The mail transport (aka Swift_Transport_MailTransport) in Swift Mailer before 5.4.5 might allow remote attackers to pass extra parameters to the mail command and consequently execute arbitrary code via a \" (backslash double quote) in a cra
How urgent is CVE-2016-10074?
Priority 69/100. Critical severity; EPSS top 1%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action