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 versions before 1.0.233 automatically confirm ZMODEM protocol detection on all terminal output without user interaction. This behavior enables an attacker to craft files that, when displayed (e.g., using cat), inject fixed byte sequences into the active PTY. These bytes are interpreted by the user's shell as commands, leading to OS command injection. Under the 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 inject commands that bypass PATH resolution. This vulnerability is addressed in Tabby version 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. This can lead to full compromise of the user's environment, including confidentiality, integrity, and availability impacts. The CVSS v3.1 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
The vulnerability is fixed in Tabby version 1.0.233. Users should upgrade to version 1.0.233 or later to remediate this issue. Patch status is not explicitly confirmed by a vendor advisory in the provided data, but the description states the issue is fixed in 1.0.233. Until upgrading, users should avoid displaying untrusted or attacker-controlled content in Tabby terminal sessions to prevent exploitation.
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.
CVSS v3.1
Score 7.0high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Tabby terminal emulator versions before 1.0.233 automatically confirm ZMODEM protocol detection on all terminal output without user interaction. This behavior enables an attacker to craft files that, when displayed (e.g., using cat), inject fixed byte sequences into the active PTY. These bytes are interpreted by the user's shell as commands, leading to OS command injection. Under the 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 inject commands that bypass PATH resolution. This vulnerability is addressed in Tabby version 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. This can lead to full compromise of the user's environment, including confidentiality, integrity, and availability impacts. The CVSS v3.1 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
The vulnerability is fixed in Tabby version 1.0.233. Users should upgrade to version 1.0.233 or later to remediate this issue. Patch status is not explicitly confirmed by a vendor advisory in the provided data, but the description states the issue is fixed in 1.0.233. Until upgrading, users should avoid displaying untrusted or attacker-controlled content in Tabby terminal sessions to prevent exploitation.
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: 5/23/2026, 6:22:42 AM
Last updated: 6/6/2026, 2:42:04 PM
Views: 46
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