CVE-2026-45036: CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') in Eugeny tabby
Tabby (formerly Terminus) is a highly configurable terminal emulator. Prior to 1.0.233, Tabby before 1.0.233 automatically confirms ZMODEM protocol detection on all terminal session output without user interaction, enabling shell command execution when a user displays attacker-controlled content. The ZModemMiddleware in tabby-terminal consumes all session output through a Zmodem.Sentry, and when a ZMODEM ZRQINIT header is detected, unconditionally calls detection.confirm() and writes a fixed ZRINIT response ( **\x18B0100000023be50\r\n\x11) back into the active PTY as input. When the process that triggered the detection (e.g., cat) exits, the injected bytes are consumed by the user's shell as a command line. Under fish (default configuration), the ** prefix triggers recursive glob expansion against the current directory, allowing an attacker-placed executable at a matching nested path (e.g., d/xB0100000023be50) to be executed by relative pathname without relying on PATH. Under bash and zsh, a secondary xterm.js terminal color-query feedback (OSC 10) can be combined in the same file to inject a slash-containing command word that similarly bypasses PATH resolution. An attacker can exploit this by providing a crafted file (e.g., in a cloned Git repository) that a user displays with cat, achieving code execution with no interaction beyond viewing the file. This vulnerability is fixed in 1.0.233.
AI Analysis
Technical Summary
Tabby terminal emulator before version 1.0.233 automatically confirms ZMODEM protocol detection on all terminal output without user interaction. This behavior allows an attacker to craft files that, when displayed by a user (e.g., via cat), inject shell commands through the ZModemMiddleware's unconditional confirmation and response writing. The injected bytes are interpreted by the shell, enabling command execution. Under fish shell, the injected prefix triggers recursive glob expansion, allowing execution of attacker-placed executables by relative path. Under bash and zsh, a secondary terminal color-query feedback can be combined to bypass PATH resolution and execute commands. This vulnerability is resolved in Tabby 1.0.233.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary shell commands on the victim's system with the privileges of the user running Tabby, simply by having the user display attacker-controlled content in the terminal. This can lead to full compromise of the user's environment. The CVSS 3.1 base score is 7.0 (High), reflecting local attack vector, high complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability is fixed in Tabby version 1.0.233. Users should upgrade to version 1.0.233 or later to remediate this issue. No vendor advisory or official patch link is provided, but the fix is confirmed in the version release notes. Until upgrading, users should avoid displaying untrusted or attacker-controlled files in Tabby terminal sessions.
CVE-2026-45036: CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') in Eugeny tabby
Description
Tabby (formerly Terminus) is a highly configurable terminal emulator. Prior to 1.0.233, Tabby before 1.0.233 automatically confirms ZMODEM protocol detection on all terminal session output without user interaction, enabling shell command execution when a user displays attacker-controlled content. The ZModemMiddleware in tabby-terminal consumes all session output through a Zmodem.Sentry, and when a ZMODEM ZRQINIT header is detected, unconditionally calls detection.confirm() and writes a fixed ZRINIT response ( **\x18B0100000023be50\r\n\x11) back into the active PTY as input. When the process that triggered the detection (e.g., cat) exits, the injected bytes are consumed by the user's shell as a command line. Under fish (default configuration), the ** prefix triggers recursive glob expansion against the current directory, allowing an attacker-placed executable at a matching nested path (e.g., d/xB0100000023be50) to be executed by relative pathname without relying on PATH. Under bash and zsh, a secondary xterm.js terminal color-query feedback (OSC 10) can be combined in the same file to inject a slash-containing command word that similarly bypasses PATH resolution. An attacker can exploit this by providing a crafted file (e.g., in a cloned Git repository) that a user displays with cat, achieving code execution with no interaction beyond viewing the file. This vulnerability is fixed in 1.0.233.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Tabby terminal emulator before version 1.0.233 automatically confirms ZMODEM protocol detection on all terminal output without user interaction. This behavior allows an attacker to craft files that, when displayed by a user (e.g., via cat), inject shell commands through the ZModemMiddleware's unconditional confirmation and response writing. The injected bytes are interpreted by the shell, enabling command execution. Under fish shell, the injected prefix triggers recursive glob expansion, allowing execution of attacker-placed executables by relative path. Under bash and zsh, a secondary terminal color-query feedback can be combined to bypass PATH resolution and execute commands. This vulnerability is resolved in Tabby 1.0.233.
Potential Impact
Successful exploitation allows an attacker to execute arbitrary shell commands on the victim's system with the privileges of the user running Tabby, simply by having the user display attacker-controlled content in the terminal. This can lead to full compromise of the user's environment. The CVSS 3.1 base score is 7.0 (High), reflecting local attack vector, high complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability is fixed in Tabby version 1.0.233. Users should upgrade to version 1.0.233 or later to remediate this issue. No vendor advisory or official patch link is provided, but the fix is confirmed in the version release notes. Until upgrading, users should avoid displaying untrusted or attacker-controlled files in Tabby terminal sessions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-08T18:07:27.340Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a075665ec166c07b0723478
Added to database: 5/15/2026, 5:22:45 PM
Last enriched: 5/15/2026, 5:36:51 PM
Last updated: 5/15/2026, 6:34:34 PM
Views: 5
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.