Sysax Multi Server: Improper Validation of Specified Quantity in Input
CVE-2023-54337 is a critical-severity improper validation of specified quantity in input vulnerability in Sysax Multi Server from Sysax, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Sysax Multi Server versions: 6.95. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.54% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Sysax Multi Server 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 |
|---|---|---|---|
| Sysax | Sysax Multi Server | 6.95 | Not stated |
| Sysax | Multi Server | 6.95 | 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
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 5.1 | Medium | CNA (vulncheck.com) |
| CVSS 3.1 | 9.1 | Critical | CNA (vulncheck.com) |
| CVSS 3.1 | 9.1 | Critical | NVD |
Official description
Sysax Multi Server 6.95 contains a denial of service vulnerability in the administrative password field that allows attackers to crash the application. Attackers can overwrite the password field with 800 bytes of repeated characters to trigger an application crash and disrupt server functionality.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Validation of Specified Quantity in Input
The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties.
More Improper Validation of Specified Quantity in Input vulnerabilities (CWE-1284)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- vulncheck.com/advisories/sysax-multi-server-password-denial-of-service-pocThird Party Advisory
Technical write-ups (may include proof of concept)
- exploit-db.com/exploits/51066Exploit, Third Party Advisory, VDB Entry
Other references
- sysax.com/Product
Recent Improper Validation of Specified Quantity in Input vulnerabilities
- 7.5 High severity
- 7.1 High severity
- 9.1 Critical severity
- 7.5 High severity
- 8.6 High severity
- 7.5 High severity
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