CVE•Published 2026-10-16•Modified 2026-10-21•0 articles on news•4 live references•NVD data

CVE-2026-96620

Vulnerability data via NVD (ingested)

CVSS v3.1

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EPSS percentile

Exploit Prediction Scoring System · top 54% of all CVEs

Weaknesses (CWE)

CWE-20Improper Input Validation CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')CWE-88Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

Description

Claude Agent SDK is a Python SDK for Claude Code. Prior to 0.2.121, the resume option is passed to the Claude CLI as a separate token without validation, so a dash-leading value is parsed as an independent CLI flag. An attacker can inject the --mcp-config flag to define a stdio MCP server, causing arbitrary command execution at CLI startup outside the SDK permission controls. The issue is exploitable when an application passes untrusted input as the session ID to resume. This issue is fixed in version 0.2.121.

Timeline

Published 2026-10-16

Modified 2026-10-21

External references

NVD MITRE Exploit-DB VulnCheck

Search for exposed instances

Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).

Shodan · vuln tag0 hosts

vuln:CVE-2026-96620

Hosts Shodan has explicitly fingerprinted as vulnerable.

More intel sources (5)

Shodan report

vuln:CVE-2026-96620

Country / ASN / product breakdown for the vuln query.

Censys

vulnerabilities.cve_id: CVE-2026-96620

Censys host search filtered to this CVE id.

grep.app

CVE-2026-96620