CVE-2026-35020
Anthropic Claude Code & Agent SDK OS Command Injection via TERMINAL Environment Variable
Description
Rejected reason: This CVE ID has been rejected by the its CVE Numbering Authority (CNA). It was determined that the attack requires an attacker to already control arbitrary environment variables, a level of access they consider functionally equivalent to code execution and outside the threat model of CLI tools.
INFO
Published Date :
April 6, 2026, 8:16 p.m.
Last Modified :
May 29, 2026, 6:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-35020
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update Anthropic Claude Code CLI.
- Update Claude Agent SDK.
- Sanitize user input for TERMINAL variable.
- Avoid shell=true when constructing commands.
Public PoC/Exploit Available at Github
CVE-2026-35020 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Run the latest security-patched @anthropic-ai/claude-code on Termux (Android, aarch64). Community-maintained wrapper for the post-v2.1.113 Termux regression. Not affiliated with Anthropic.
Shell JavaScript C
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-35020 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-35020 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Rejected by [email protected]
May. 29, 2026
Action Type Old Value New Value -
CVE Modified by [email protected]
May. 29, 2026
Action Type Old Value New Value Removed Tag VulnCheck: disputed Changed Description Anthropic Claude Code CLI and Claude Agent SDK contain an OS command injection vulnerability in the command lookup helper and deep-link terminal launcher that allows local attackers to execute arbitrary commands by manipulating the TERMINAL environment variable. Attackers can inject shell metacharacters into the TERMINAL variable which are interpreted by /bin/sh when the command lookup helper constructs and executes shell commands with shell=true. The vulnerability can be triggered during normal CLI execution as well as via the deep-link handler path, resulting in arbitrary command execution with the privileges of the user running the CLI. Rejected reason: This CVE ID has been rejected by the its CVE Numbering Authority (CNA). It was determined that the attack requires an attacker to already control arbitrary environment variables, a level of access they consider functionally equivalent to code execution and outside the threat model of CLI tools. Removed CVSS V4.0 VulnCheck: AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Removed CVSS V3.1 VulnCheck: AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Removed CWE VulnCheck: CWE-78 Removed CPE Configuration OR *cpe:2.3:a:anthropic:claude_code:*:*:*:*:*:node.js:*:* versions up to (including) 2.1.91 *cpe:2.3:a:anthropic:claude_agent_sdk:*:*:*:*:*:python:*:* versions up to (including) 0.1.55 Removed Reference VulnCheck: https://phoenix.security/critical-ci-cd-nightmare-3-command-injection-flaws-in-claude-code-cli-allow-credential-exfiltration/ Removed Reference VulnCheck: https://www.vulncheck.com/advisories/anthropic-claude-code-agent-sdk-os-command-injection-via-terminal-environment-variable Removed Reference Type VulnCheck: https://phoenix.security/critical-ci-cd-nightmare-3-command-injection-flaws-in-claude-code-cli-allow-credential-exfiltration/ Types: Exploit, Third Party Advisory Removed Reference Type VulnCheck: https://www.vulncheck.com/advisories/anthropic-claude-code-agent-sdk-os-command-injection-via-terminal-environment-variable Types: Third Party Advisory -
Initial Analysis by [email protected]
Apr. 29, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:anthropic:claude_code:*:*:*:*:*:node.js:*:* versions up to (including) 2.1.91 *cpe:2.3:a:anthropic:claude_agent_sdk:*:*:*:*:*:python:*:* versions up to (including) 0.1.55 Added Reference Type VulnCheck: https://phoenix.security/critical-ci-cd-nightmare-3-command-injection-flaws-in-claude-code-cli-allow-credential-exfiltration/ Types: Exploit, Third Party Advisory Added Reference Type VulnCheck: https://www.vulncheck.com/advisories/anthropic-claude-code-agent-sdk-os-command-injection-via-terminal-environment-variable Types: Third Party Advisory -
CVE Modified by [email protected]
Apr. 13, 2026
Action Type Old Value New Value Added Tag disputed -
New CVE Received by [email protected]
Apr. 06, 2026
Action Type Old Value New Value Added Description Anthropic Claude Code CLI and Claude Agent SDK contain an OS command injection vulnerability in the command lookup helper and deep-link terminal launcher that allows local attackers to execute arbitrary commands by manipulating the TERMINAL environment variable. Attackers can inject shell metacharacters into the TERMINAL variable which are interpreted by /bin/sh when the command lookup helper constructs and executes shell commands with shell=true. The vulnerability can be triggered during normal CLI execution as well as via the deep-link handler path, resulting in arbitrary command execution with the privileges of the user running the CLI. Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-78 Added Reference https://phoenix.security/critical-ci-cd-nightmare-3-command-injection-flaws-in-claude-code-cli-allow-credential-exfiltration/ Added Reference https://www.vulncheck.com/advisories/anthropic-claude-code-agent-sdk-os-command-injection-via-terminal-environment-variable