Security readout for executives and security teams
Plain-English summary
A public Powermail form may let an unauthenticated attacker make the server interpret sender-name input as a template. Successful abuse could expose secrets, configuration, environment variables, and source code, with possible remote code execution. Exposure depends on the installed Powermail version and whether a form field is configured as sender_name.
Executive priority
Treat this as an immediate incident-response and remediation priority for internet-facing TYPO3 systems. The attack is unauthenticated, the vulnerable configuration is described as common, and impact may include secret theft or server compromise. Owners should establish exposure today, restrict vulnerable forms, follow vendor remediation, and investigate affected systems for prior abuse.
Technical view
Powermail passes raw sender_name field content into a TYPO3 Fluid View as template source without sanitization. An attacker can submit Fluid syntax that invokes ViewHelpers. The supplied CVSS 4.0 score is 9.5, reflecting network access, low complexity, no privileges, no user interaction, and potentially extensive confidentiality, integrity, and availability impact.
Likely exposure
Internet-facing TYPO3 sites using in2code/powermail require urgent review, especially forms configured with a sender_name field. The bundle lists version markers 13.0.0, 11.0.0, and 0, but does not clearly define affected ranges. Confirm exact exposure using the vendor advisory rather than interpreting these markers as complete ranges.
Exploitation context
The supplied CVE description reports active exploitation in the wild. However, the CVE is not listed as KEV in this bundle, and no independent corroborating evidence is included. Exploitation requires a form using sender_name but otherwise needs no authentication or interaction beyond submitting that form.
Researcher notes
CWE-1336 fits server-side template injection. The prerequisite represented by AT:P is the sender_name form configuration. Arbitrary Fluid ViewHelper execution is stated; remote code execution is described as potential, not guaranteed. Exact version boundaries, fixed releases, indicators, and technical mitigations are absent from the supplied details and must be obtained from the vendor advisory.
Mitigation direction
- Inventory all TYPO3 deployments containing the in2code/powermail package and record deployed versions.
- Identify and temporarily restrict affected public forms using a sender_name field.
- Consult the TYPO3 advisory and apply its vendor-confirmed fixed release or mitigation immediately.
- If compromise is suspected, isolate affected systems and rotate potentially exposed credentials and secrets.
- Preserve relevant logs and begin incident-response review before rebuilding or restoring affected systems.
Validation and detection
- Compare each deployed Powermail version with the exact affected ranges in the TYPO3 advisory.
- Enumerate forms configured with sender_name and determine whether anonymous users can reach them.
- Review form submissions and application logs for unexpected Fluid syntax or anomalous ViewHelper activity.
- Assess whether configuration, environment variables, source code, or credentials may have been exposed.
- After remediation, confirm affected forms no longer render submitted sender-name values as template source.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-1336: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-77136 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.5 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H——TYPO3Vulnerability scoring details
Base CVSS 4.0 score
9.5CriticalVector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://typo3.org/security/advisory/typo3-ext-sa-2026-022CVE reference, TYPO3 · vendor-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Special Elements Used in a Template Engine
Improper Neutralization of Special Elements Used in a Template Engine represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.