CVE-2026-77136
Server-Side Template Injection in extension "powermail" (powermail)
Description
The extension passes the raw value of a form field configured as "This field contains the name of the sender" directly into a Fluid View as template source, without any sanitization, and renders it. An anonymous, unauthenticated user can submit Fluid template syntax in that field to execute arbitrary Fluid ViewHelpers leading to disclosure of server configuration, environment variables and application source, and potentially remote code execution. Exploitation requires only that a form field is configured as the sender_name field, a common and default-adjacent Powermail configuration. No authentication or user interaction beyond a normal form submission is required. This vulnerability is reported to be actively exploited in the wild.
INFO
Published Date :
Aug. 25, 2026, 9:17 a.m.
Last Modified :
Aug. 25, 2026, 9:17 a.m.
Remotely Exploit :
Yes !
Source :
f4fb688c-4412-4426-b4b8-421ecf27b14a
Affected Products
The following products are affected by CVE-2026-77136
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | CRITICAL | f4fb688c-4412-4426-b4b8-421ecf27b14a | ||||
| CVSS 4.0 | CRITICAL | f4fb688c-4412-4426-b4b8-421ecf27b14a |
Solution
- Sanitize all input used as Fluid template source.
- Restrict usage of sensitive ViewHelpers.
- Update the extension to the latest version.
- Review Powermail configurations for sender_name.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-77136.
| URL | Resource |
|---|---|
| https://typo3.org/security/advisory/typo3-ext-sa-2026-022 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-77136 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-77136
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-77136 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-77136 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by f4fb688c-4412-4426-b4b8-421ecf27b14a
Aug. 25, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/in2code-de/powermail', 'vendor': 'TYPO3', 'product': 'Extension "powermail"', 'versions': [{'status': 'affected', 'version': '13.0.0', 'lessThan': '13.2.1', 'versionType': 'semver'}, {'status': 'affected', 'version': '11.0.0', 'lessThan': '12.6.1', 'versionType': 'semver'}, {'status': 'affected', 'version': '0', 'lessThan': '10.9.3', 'versionType': 'semver'}], 'packageName': 'in2code/powermail', 'collectionURL': 'https://packagist.org/', 'defaultStatus': 'unaffected'}] Added Description The extension passes the raw value of a form field configured as "This field contains the name of the sender" directly into a Fluid View as template source, without any sanitization, and renders it. An anonymous, unauthenticated user can submit Fluid template syntax in that field to execute arbitrary Fluid ViewHelpers leading to disclosure of server configuration, environment variables and application source, and potentially remote code execution. Exploitation requires only that a form field is configured as the sender_name field, a common and default-adjacent Powermail configuration. No authentication or user interaction beyond a normal form submission is required. This vulnerability is reported to be actively exploited in the wild. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-1336 Added Reference https://typo3.org/security/advisory/typo3-ext-sa-2026-022