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.

Scores

EPSS (exploitation in 30 days)

0.97% · top 38% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: total

The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.5.

Weakness

• CWE-1336 Improper Neutralization of Special Elements Used in a Template Engine (opens in a new tab)All about CWE-1336 and its CVEs

Affected products

• TYPO3 · Extension "powermail"

  • affected 13.0.0 – < 13.2.1
  • affected 11.0.0 – < 12.6.1
  • affected < 10.9.3

References (1)

• https://typo3.org/security/advisory/typo3-ext-sa-2026-022 (opens in a new tab)vendor-advisory

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-77136](https://trackcve.app/badge/CVE-2026-77136.svg)](https://trackcve.app/cve/CVE-2026-77136)

Record last updated 25 Aug 2026, 14:07 UTC.