CVE-2026-100563 in OpenClaw
Summary
by MITRE • 09/26/2026
OpenClaw (npm package `openclaw`) before 2026.8.1 does not neutralize leading characters that spreadsheet applications interpret as formulas when the Control UI exports session data to CSV. Although session labels were quoted as CSV text, a lower-trust participant who can influence a session label or the first user message can place a formula-like cell in the Usage export; if an operator opens that export in a spreadsheet application with formula evaluation enabled, the cell may be evaluated with the permissions of the spreadsheet user. OpenClaw itself does not evaluate the formula, and practical impact depends on the spreadsheet application's security settings. The issue is fixed in 2026.8.1.
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Analysis
by VulDB Data Team • 09/26/2026
The vulnerability identified within versions of the openclaw npm package prior to release 2026.8.1 constitutes a classic CSV injection flaw, technically categorized under CWE-74 as Injection Errors and more specifically aligned with CWE-935 as Improper Neutralization of Special Elements in Data Sent to Users via Web Application. This security defect arises from the application's handling of session metadata during the export process for usage reports. When users generate CSV exports containing session labels or initial user messages, the software fails to properly sanitize input strings that begin with characters commonly interpreted by spreadsheet applications as formula initiators, such as equals signs, plus signs, minus signs, at symbols, and tab characters. Although the developers implemented a mitigation strategy by quoting these fields as standard CSV text values, this approach is insufficient against modern spreadsheet parsers which often automatically interpret leading special characters regardless of surrounding quotes if specific parsing heuristics are triggered or if the user manually edits the cell to remove the enclosing quotes.
The operational impact of this vulnerability centers on Client-Side Code Injection via Spreadsheet Applications. An attacker with lower trust privileges, such as a participant in a shared session who can influence the session label or the content of the first message sent within that session, can inject malicious payloads into the exported data file. These payloads are designed to exploit the automatic formula evaluation features present in popular spreadsheet software like Microsoft Excel, Google Sheets, and LibreOffice Calc. If an operator opens the compromised CSV export with formula evaluation enabled, which is often the default behavior for security-conscious but automated workflows or users who trust their source files, the injected command will execute within the context of the user's local environment. This execution occurs entirely on the client side, meaning OpenClaw itself does not process or evaluate these formulas; rather, the vulnerability relies on the downstream consumer of the data to inadvertently act as the execution engine for the malicious code.
The practical severity of this exploit is contingent upon the security configuration and awareness level of the end-user opening the file. While modern spreadsheet applications frequently display warning dialogs when detecting external connections or macro-enabled content, sophisticated attackers can craft payloads that perform less obvious but still damaging actions. These may include reading local files via functions like VLOOKUP combined with UNC path injection to exfiltrate data from network shares, sending HTTP requests to remote servers controlled by the attacker using DDE (Dynamic Data Exchange) protocols, or even triggering arbitrary command execution on Windows systems through specific macro-enabled CSV tricks that bypass standard security prompts. The lack of strict neutralization means that any sensitive information contained within session labels or initial messages can be weaponized if those fields are manipulated to contain formula syntax, turning routine administrative tasks like reviewing usage logs into potential vectors for system compromise.
To mitigate this vulnerability, organizations must immediately upgrade the openclaw package to version 2026.8.1 or later, where the developers have implemented proper neutralization of leading special characters in exported CSV fields. This typically involves prefixing potentially dangerous values with a single quote character or using alternative escaping mechanisms that prevent spreadsheet parsers from interpreting the content as executable code. In addition to applying this patch, security teams should enforce strict data handling policies regarding CSV exports, ensuring that users are aware of the risks associated with opening untrusted files in applications capable of formula evaluation. It is also advisable to configure spreadsheet software settings where possible to disable automatic macro execution and external connection prompts by default, thereby reducing the attack surface for client-side injection attacks. Regular security training should emphasize the importance of verifying file sources before opening them, particularly when dealing with data exported from collaborative platforms that may contain user-generated content susceptible to such manipulation techniques aligned with ATT&CK technique T1059 Command and Scripting Interpreter or T1204 User Execution depending on the specific payload utilized.