User-assisted code execution via unescaped shell metacharacters
Published Apr 29, 2025 · Updated Apr 13, 2026
Command injection in Mozilla Firefox and Thunderbird before 138 allows attackers to execute local code through copied cURL commands. DevTools Netmonitor serializes attacker-controlled request data without escaping shell metacharacters, allowing command separators to survive in the generated command. Exploitation requires a user to copy the malicious request as cURL and execute the resulting command in a local shell.
Summary
What happened
Command injection in Mozilla Firefox and Thunderbird before 138 allows attackers to execute local code through copied cURL commands. DevTools Netmonitor serializes attacker-controlled request data without escaping shell metacharacters, allowing command separators to survive in the generated command. Exploitation requires a user to copy the malicious request as cURL and execute the resulting command in a local shell.
The record
- CVE
- CVE-2025-4089
- Published
- Apr 29, 2025
- Updated
- Apr 13, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-77, T1204.004
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 29, 2025CVE publishedPublication date reported by the CVE source.
- Apr 13, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Copy as cURL shell-metacharacter proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo