CVE-2017-18343

Public Exploit

Description

The debug handler in Symfony before v2.7.33, 2.8.x before v2.8.26, 3.x before v3.2.13, and 3.3.x before v3.3.6 has XSS via an array key during exception pretty printing in ExceptionHandler.php, as demonstrated by a /_debugbar/open?op=get URI. NOTE: the vendor's position is that this is not a vulnerability because the debug tools are not intended for production use. NOTE: the Symfony Debug component is used by Laravel Debugbar

Category

6.1
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.52%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/symfony/symfony/pull/23684 third party advisory
https://github.com/symfony/debug/pull/7/commits/e48bda29143bd1a83001780b4a78e483822d985c third party advisory patch
https://github.com/symfony/symfony/issues/27987 third party advisory exploit
https://github.com/barryvdh/laravel-debugbar/issues/850 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2017-18343?
CVE-2017-18343 has been scored as a medium severity vulnerability.
How to fix CVE-2017-18343?
To fix CVE-2017-18343, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2017-18343 being actively exploited in the wild?
It is possible that CVE-2017-18343 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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