Ember TUI passes terminal escape sequences from Caddy logs
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.
Summary
Ember before 1.4.2 passes Caddy access-log fields, including the request URI, to its TUI without neutralizing terminal control sequences (CWE-150). An unauthenticated remote client can place control bytes in an HTTP request target that the terminal interprets when the operator views the Logs tab. This enables dashboard spoofing, clipboard hijacking through OSC 52 and window-title spoofing through OSC 0 and OSC 2.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
Ember is a real-time terminal dashboard for Caddy servers with FrankenPHP support. Prior to 1.4.2, interactive TUI row formatters pass Caddy access-log fields, particularly the request URI, through the `fitCellLeft` render helper without neutralizing terminal escape or control sequences. An unauthenticated remote client can place ANSI, OSC, or CSI control bytes in an ordinary HTTP request target. Caddy JSON-escapes those bytes, `ParseLogLine` decodes them back into raw controls, and the formatters concatenate them into `View()` output reaching `os.Stdout`. When the operator views the default `Logs` tab, the terminal interprets these sequences, allowing monitoring-dashboard spoofing, clipboard hijacking through `OSC 52`, and window-title spoofing through `OSC 0/2`. This works even with a loopback-only log listener because the input arrives through normal Caddy access logs. `Certificates` and `Routes` share secondary unneutralized render sinks. The `--json`, `--once`, and daemon `--expose` modes are unaffected because they do not render an interactive terminal. Consequences depend on the terminal emulator and usually require further operator action to escalate; this is not general-purpose remote code execution. This issue is fixed in version 1.4.2.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| alexandre-daubois | ember | before 1.4.2 | 1.4.2 | Patch available | CNA |
| — | github.com/alexandre-daubois/ember (Go) | before 1.4.2 | 1.4.2 | Patch available | GHSA-x3g7-qrwc-f6c5 |
- ember Vendoralexandre-daubois Affected before 1.4.2 Fixed in 1.4.2 Patch available CNA
- github.com/alexandre-daubois/ember (Go) Vendor— Affected before 1.4.2 Fixed in 1.4.2 Patch available GHSA-x3g7-qrwc-f6c5
Remediation
Upgrade Ember to version 1.4.2, which fixes this issue for the github.com/alexandre-daubois/ember Go module.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
- Fix · CNA ember (alexandre-daubois) Fixed in 1.4.2
- Fix · GHSA-x3g7-qrwc-f6c5 github.com/alexandre-daubois/ember (Go) Fixed in 1.4.2 Advisory →
Timeline
- 2026-10-28 Threatist record created from CVE-2026-54162
- 2026-10-29 CISA SSVC decision points changed
References
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences