CVE-2021-39339

Telefication <= 1.8.0 - Open Relay and Server-Side Request Forgery

2021-09-21 15:31

Strategic Overview

Status: Unpatched
Affected Plugin: Telefication
Affected Version: <= 1.8.0
CVSS: 5.8Medium
Weakness type: CWE-918 · Server-Side Request Forgery (SSRF)
CVE: CVE-2021-39339

At a glance

CVE-2021-39339 is a medium-severity Server-Side Request Forgery (SSRF) vulnerability in the Telefication WordPress plugin, affecting versions <= 1.8.0. It carries a CVSS score of 5.8 (reachable over the network; low attack complexity). Exploitation requires no authentication. No fixed release has been reported yet; treat installations running this software as exposed. Disclosed September 2021, reported by Charles Strader Sweethill.

Vulnerability Overview

The Telefication WordPress plugin is vulnerable to Open Proxy and Server-Side Request Forgery via the ~/bypass.php file due to a user-supplied URL request value that gets called by a curl requests. This affects versions up to, and including, 1.8.0.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-918: Server-Side Request Forgery (SSRF)

Reaching this weakness in Telefication <= 1.8.0 takes a caller who can reach the endpoint. Server-side request forgery means the application fetches a URL supplied by the caller, turning the server into a proxy for requests the attacker could not make directly.

The request originates from inside the hosting network, which is how these flaws reach cloud metadata endpoints, internal admin panels and services that trust local traffic. No fixed build of this plugin is recorded for Telefication yet, so installs running <= 1.8.0 stay exposed until the vendor ships one.

Remediation

No known patch available. Please review the vulnerability's details in depth and employ mitigations based on your organization's risk tolerance. It may be best to uninstall the affected software and find a replacement.

How does WordSec protect against this?

The attempt arrives as an ordinary request to Telefication: WordSec's web application firewall inspects request payloads before WordPress loads them. No patched version is recorded yet, which is the case where a filtering layer matters most, because there is nothing to update to.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2021-39339 https://www.wordfence.com/threat-intel/vulnerabilities/id/d9f1719c-ef66-4c68-b25c-175c99938e7a https://nvd.nist.gov/vuln/detail/CVE-2021-39339

CVSS Vector

5.8

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

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeChanged
ConfidentialityNone
IntegrityNone
AvailabilityLow

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