growthbook: Improper Limitation of a Pathname to a Restricted Directory
CVE-2022-36065 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in growthbook, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected growthbook versions: < 2022-08-29. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.46% chance of exploitation within 30 days, higher than 74% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of growthbook 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
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Growthbook | growthbook | < 2022-08-29 | Not stated |
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
- HighSuccess depends on conditions outside the attacker's control.
- 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:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | CNA (github.com) |
| CVSS 3.1 | 7.5 | High | NVD |
Official description
GrowthBook is an open-source platform for feature flagging and A/B testing. With some self-hosted configurations in versions prior to 2022-08-29, attackers can register new accounts and upload files to arbitrary directories within the container. If the attacker uploads a Python script to the right location, they can execute arbitrary code within the container. To be affected, ALL of the following must be true: Self-hosted deployment (GrowthBook Cloud is unaffected); using local file uploads (as opposed to S3 or Google Cloud Storage); NODE_ENV set to a non-production value and JWT_SECRET set to an easily guessable string like `dev`. This issue is patched in commit 1a5edff8786d141161bf880c2fd9ccbe2850a264 (2022-08-29). As a workaround, set `JWT_SECRET` environment variable to a long random string. This will stop arbitrary file uploads, but the only way to stop attackers from registering accounts is by updating to the latest build.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
How developers prevent this class of flaw
- 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.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)
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
- github.com/growthbook/growthbook/security/advisories/GHSA-j24q-55xh-wm4rIssue Tracking, Mitigation, Third Party Advisory
Patches and release notes
- github.com/growthbook/growthbook/commit/1a5edff8786d141161bf880c2fd9ccbe2850a264Third Party Advisory
- github.com/growthbook/growthbook/pull/487Issue Tracking, Mitigation, Third Party Advisory
Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities
- 8.6 High severity
- 9.8 Critical severity
- 7.8 High severity
- 7.5 High severity
- 7.8 High severity
- 7.5 High severity
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