Mozilla VPN: Unrestricted Upload of File with Dangerous Type
CVE-2022-0517 is a high-severity unrestricted upload of file with dangerous type vulnerability in Mozilla VPN from Mozilla, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 2.7.1 as the first without the flaw, so updating Mozilla VPN to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.19% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Mozilla VPN to 2.7.1 or a later version.
- Update VPN to 2.7.1 or a later version.
- Read the advisory on bugzilla.mozilla.org for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Mozilla | Mozilla VPN | before 2.7.1 | 2.7.1 |
| Mozilla | VPN | before 2.7.1 | 2.7.1 |
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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- 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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | NVD |
| CVSS 3.1 | 7.8 | High | CISA (ADP) |
Official description
Mozilla VPN can load an OpenSSL configuration file from an unsecured directory. A user or attacker with limited privileges could leverage this to launch arbitrary code with SYSTEM privilege. This vulnerability affects Mozilla VPN < 2.7.1.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Unrestricted Upload of File with Dangerous Type
The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
How developers prevent this class of flaw
- Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.
- When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
- Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically.
More Unrestricted Upload of File with Dangerous Type vulnerabilities (CWE-434)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- bugzilla.mozilla.org/show_bug.cgi?id=1752291Issue Tracking, Permissions Required
- mozilla.org/security/advisories/mfsa2022-08/
Recent Unrestricted Upload of File with Dangerous Type vulnerabilities
- 7.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.2 High severity
- 7.8 High severity
- 8.8 High severity
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