Is CVE-2017-5553 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2017-5553 being exploited in the wild.

How severe is CVE-2017-5553?

Medium severity, with a CVSS score of 5.4, published 23 January 2017.

Which products and versions are affected?

b2evolution b2evolution before 6.8.5.

Is there a fix for CVE-2017-5553?

A patch was published on 2017-01-19: Version 6.8.5 released with security fixes. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2017-5553 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2017-5553?

Check whether you run B2evolution. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2017-5553: b2evolution XSS in Markdown plugin

CVE-2017-5553 · Severity: medium · CVSS 5.4 · Published 2017-01-23

b2evolution is a content management system used to host blogs and community websites. A security flaw in its Markdown plugin allows registered users to embed malicious scripts into posts or comments. If another user or administrator views this content, the script could execute in their browser, potentially leading to unauthorized actions or data theft.

Technologies: B2evolution. Vendors: B2evolution.

Quick answers

Is CVE-2017-5553 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2017-5553 being exploited in the wild.
How severe is CVE-2017-5553?: Medium severity, with a CVSS score of 5.4, published 23 January 2017.
Which products and versions are affected?: b2evolution b2evolution before 6.8.5.
Is there a fix for CVE-2017-5553?: A patch was published on 2017-01-19: Version 6.8.5 released with security fixes. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2017-5553 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2017-5553?: Check whether you run B2evolution. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A stored cross-site scripting (XSS) vulnerability exists in plugins/markdown_plugin/_markdown.plugin.php (specifically involving _parsedown.inc.php) in b2evolution versions prior to 6.8.5. The Markdown parser fails to properly validate or sanitize URLs used in links and images, allowing the use of the 'javascript:' URI scheme. An authenticated attacker can exploit this by creating content containing these malicious links; when a victim clicks the link or views the rendered page, arbitrary JavaScript executes in the context of their session. The fix implemented in version 6.8.5 restricts allowed URL schemes to http://, https://, or relative paths starting with /.

Affected products

b2evolution b2evolution before 6.8.5

Timeline

2017-01-19: patched: Version 6.8.5 released with security fixes.
2017-01-23: disclosed: NVD publication date.

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.