CVE-2017-20207

Dancoulter Flickr Gallery insecure deserialization

9.8 CRITICALEPSS 0.73%

Published18 Oct 2025

Description

The Flickr Gallery plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 1.5.2 via deserialization of untrusted input from the `pager ` parameter. This allows unauthenticated attackers to inject a PHP Object. Attackers were actively exploiting this vulnerability with the WP_Theme() class to create backdoors.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Dancoulter Flickr Gallery≤ 1.5.2

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

Patch & vendor advisories

https://plugins.trac.wordpress.org/changeset/1737576/flickr-gallery

References

https://plugins.trac.wordpress.org/changeset/1737576/flickr-galleryPatch
https://www.wordfence.com/blog/2017/10/3-zero-day-plugin-vulnerabilities-exploited-wild/Press/Media CoverageThird Party Advisory
https://www.wordfence.com/threat-intel/vulnerabilities/id/b52ae51d-7b9a-4047-82bf-723ea87d2375?source=cveThird Party Advisory

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2017-20207 being actively exploited?

CVE-2017-20207 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.73%.

How severe is CVE-2017-20207?

CVE-2017-20207 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.73% probability of exploitation.

Which products are affected by CVE-2017-20207?

Affected products include Dancoulter Flickr Gallery.

How do I fix CVE-2017-20207?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2017-20207 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation works Book a demo

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.