pinchtab: Improper Neutralization of Special Elements used in an OS Command
CVE-2026-33623 is a high-severity improper neutralization of special elements used in an OS command vulnerability in pinchtab, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected pinchtab versions: < 0.8.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 3.08% chance of exploitation within 30 days, higher than 88% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of pinchtab you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 6.7 | Medium | CNA (github.com) |
| CVSS 3.1 | 7.2 | High | NVD |
Official description
PinchTab is a standalone HTTP server that gives AI agents direct control over a Chrome browser. PinchTab `v0.8.4` contains a Windows-only command injection issue in the orphaned Chrome cleanup path. When an instance is stopped, the Windows cleanup routine builds a PowerShell `-Command` string using a `needle` derived from the profile path. In `v0.8.4`, that string interpolation escapes backslashes but does not safely neutralize other PowerShell metacharacters. If an attacker can launch an instance using a crafted profile name and then trigger the cleanup path, they may be able to execute arbitrary PowerShell commands on the Windows host in the security context of the PinchTab process user. This is not an unauthenticated internet RCE. It requires authenticated, administrative-equivalent API access to instance lifecycle endpoints, and the resulting command execution inherits the permissions of the PinchTab OS user rather than bypassing host privilege boundaries. Version 0.8.5 contains a patch for the issue.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in an OS Command
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.
How developers prevent this class of flaw
- If at all possible, use library calls rather than external processes to recreate the desired functionality.
- For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/pinchtab/pinchtab/security/advisories/GHSA-p8mm-644p-phmhExploit, Mitigation
Patches and release notes
Other vulnerabilities in pinchtab
- 8.8 High severity
- 7.5 High severity
Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 9.9 Critical severity
- 8.8 High severity
- 8.8 High severity
- 7.2 High severity
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