GHSA-r9mw-gwx9-v3h5 — zendframework/zend-mail
CRITICALGHSA-r9mw-gwx9-v3h5 is a critical-severity (CVSS 9.8) CWE-77 vulnerability in zendframework/zend-mail. 5 public exploit references exist, so weaponization risk is real. A fix is available for zendframework/zend-mail — see the affected versions and patch details below.
zend-mail remote code execution via Sendmail adapter
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-r9mw-gwx9-v3h5 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
zendframework/zend-mail🐘zendframework/zend-mail🐘zendframework/zend-mail🐘zendframework/zend-mailReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
The setFrom function in the Sendmail adapter in the zend-mail component before 2.4.11, 2.5.x, 2.6.x, and 2.7.x before 2.7.2, and Zend Framework before 2.4.11 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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | zendframework/zend-mail | all versions | 2.4.11composer require zendframework/zend-mail:^2.4.11 |
| 🐘Packagist | zendframework/zend-mail | ≥ 2.5 | No fix |
| 🐘Packagist | zendframework/zend-mail | ≥ 2.6 | No fix |
| 🐘Packagist | zendframework/zend-mail | ≥ 2.7&&< 2.7.2 | 2.7.2composer require zendframework/zend-mail:^2.7.2 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
PHPMailer < 5.2.20 / SwiftMailer < 5.4.5-DEV / Zend Framework / zend-mail < 2.4.11 - 'AIO' 'PwnScriptum' Remote Code Execution
by Dawid Golunski · Jan 2, 2017
PHPMailer < 5.2.20 with Exim MTA - Remote Code Execution
by phackt_ul · Jun 21, 2017
Zend Framework / zend-mail < 2.4.11 - Remote Code Execution
by Dawid Golunski · Dec 30, 2016
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for zendframework/zend-mail, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update zendframework/zend-mail to 2.4.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-r9mw-gwx9-v3h5 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-r9mw-gwx9-v3h5 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-r9mw-gwx9-v3h5. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-r9mw-gwx9-v3h5 in your dependencies?
O3 Security finds GHSA-r9mw-gwx9-v3h5 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.