VOS: Use of Hard-coded Credentials
CVE-2026-107243 is a high-severity use of hard-coded credentials vulnerability in VOS from Versa, with a CVSS 3.0 base score of 7.6 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, but only if a user takes part, for example by opening a link or file. The record lists versions July 2, 2026, Aug 3, 2026 as the first without the flaw, so updating VOS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.29% 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 VOS to July 2, 2026 or Aug 3, 2026, whichever matches your release line, or a later version.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Versa | VOS | 21.1.1 through 21.2.3; 22.1.2 up to, but not including, July 2, 2026; 22.1.3 up to, but not including, July 2, 2026; 22.1.4 up to, but not including, July 2, 2026; 23.1.2 up to, but not including, Aug 3, 2026 | July 2, 2026, Aug 3, 2026 |
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
- HighAdministrator-level access is required first.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- 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:3.0/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:H. Scored by CNA (hackerone.com).
Official description
The Node.js web service on VOS (previously Versa FlexVNF) is used for URL-based Zero Touch Provisioning (ZTP) of the VOS appliance and is not required after provisioning is complete. The express-session middleware in server.js is configured with a hardcoded secret that is identical across all VOS appliances and is used to sign session cookies. An attacker who obtains a valid session ID from any source can compute the correct HMAC-SHA256 signature and forge a session cookie that the server accepts as legitimate. Because the secret is shared across all VOS appliances, a forged cookie is accepted by any VOS appliance in the deployment. Versa’s security hardening guide for Hubs, Branches, and Controllers recommends disabling the Node.js web service after the initial provisioning of the VOS device. This vulnerability is not exploitable on VOS devices where the Node.js web service has been disabled.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use of Hard-coded Credentials
The product contains hard-coded credentials, such as a password or cryptographic key.
How developers prevent this class of flaw
- For outbound authentication: store passwords, keys, and other credentials outside of the code in a strongly-protected, encrypted configuration file or database that is protected from access by all outsiders, including other local users on the same system. Properly protect the key (CWE-320). If you cannot use encryption to protect the file, then make sure that the permissions are as restrictive as possible. In Windows environments, the Encrypted File System (EFS) may provide some protection.
- For inbound authentication: Rather than hard-code a default username and password, key, or other authentication credentials for first time logins, utilize a first login mode that requires the user to enter a unique strong password or key.
- If the product must contain hard-coded credentials or they cannot be removed, perform access control checks and limit which entities can access the feature that requires the hard-coded credentials. For example, a feature might only be enabled through the system console instead of through a network connection.
More Use of Hard-coded Credentials vulnerabilities (CWE-798)
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
Other vulnerabilities in VOS
- 7.5 High severity
- 7.6 High severity
- 9.1 Critical severity
- 7.6 High severity
- 7.6 High severity
Recent Use of Hard-coded Credentials vulnerabilities
- 8.8 High severity
- 9.8 Critical severity
- 7.8 High severity
- 7.2 High severity
- 8.1 High severity
- 9.0 Critical severity
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