Bert-VITS2: Improper Limitation of a Pathname to a Restricted Directory
CVE-2026-8755 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in Bert-VITS2 from FishAudio, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Bert-VITS2 versions: 8f7fbd8c4770965225d258db548da27dc8dd934c. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.61% 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
- Check which version of Bert-VITS2 you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Fishaudio | Bert-VITS2 | 8f7fbd8c4770965225d258db548da27dc8dd934c | 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
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- LowSome restricted data can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L. Scored by CNA (vuldb.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 5.5 | Medium | CNA (vuldb.com) |
| CVSS 3.1 | 7.3 | High | CNA (vuldb.com) |
| CVSS 2.0 | 7.5 | High | CNA (vuldb.com) |
Official description
A flaw has been found in fishaudio Bert-VITS2 up to 8f7fbd8c4770965225d258db548da27dc8dd934c. The affected element is the function _get_all_models of the file hiyoriUI.py of the component Model Handler. This manipulation causes path traversal. The attack can be initiated remotely. The exploit has been published and may be used. Continious delivery with rolling releases is used by this product. Therefore, no version details of affected nor updated releases are available. The vendor was contacted early about this disclosure but did not respond in any way.
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: poc, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in Bert-VITS2
- 7.3 High severity
- 9.8 Critical severity
- 9.8 Critical severity
Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities
- 9.1 Critical severity
- 9.8 Critical severity
- 8.1 High severity
- 7.1 High severity
- 9.2 Critical severity
- 7.5 High severity
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