CVE-2021-39339Network attack vector

Unauthenticated request relay via unchecked cURL destination

Published Sep 22, 2021 · Updated Mar 31, 2025

Server-side request forgery in Telefication 1.8.0 and earlier allows remote attackers to relay requests through the WordPress server. The bypass.php script passes a user-supplied URL directly to a cURL request without validating or restricting the destination. No authentication or user interaction is required, and the server can contact attacker-chosen endpoints, act as an open proxy, and experience service interruption.

CVSS severity5.8
Medium
EPSS probability1.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Server-side request forgery in Telefication 1.8.0 and earlier allows remote attackers to relay requests through the WordPress server. The bypass.php script passes a user-supplied URL directly to a cURL request without validating or restricting the destination. No authentication or user interaction is required, and the server can contact attacker-chosen endpoints, act as an open proxy, and experience service interruption.

The record

CVE
CVE-2021-39339
Published
Sep 22, 2021
Updated
Mar 31, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-918, T1090
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 22, 2021CVE publishedPublication date reported by the CVE source.
  2. Mar 31, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.8WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1090Proxy

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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