CVE-2026-77136: Server-Side Template Injection in extension "powermail" (powermail)
- Is it exploited?
Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of .
VulnCheck KEV lists it since . It cites 2 public reports, the first from .
- How likely is exploitation in the next 30 days?
- 1%
EPSS score, percentile 61.8 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.5 Critical
CVSS v4.0 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
- Which versions are affected?
Affected
- from 13.0.0 to before 13.2.1
- from 11.0.0 to before 12.6.1
- before 10.9.3
Source: CISA KEV 2026.10.29, as of ; VulnCheck KEV, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
Description
Server-Side Template Injection in extension "powermail" (powermail)
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.
Source: CVE List, as of . About the data.
What to do
Advisories and patches
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
Versions by product, as listed in the CVE record (1 product)
| Status | Versions |
|---|---|
| Affected | from 13.0.0 to before 13.2.1 |
| Affected | from 11.0.0 to before 12.6.1 |
| Affected | before 10.9.3 |
Versions not listed are: unaffected.
Source: CVE List, as of . About the data.
Weakness
CWE-1336
- CWE-1336: Improper Neutralization of Special Elements Used in a Template Engine
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.
Timeline
| Date | Event |
|---|---|
| CVE record published |