SINEMA Remote Connect Server: Creation of Temporary File With Insecure Permissions
CVE-2024-39872 is a critical-severity creation of temporary file with insecure permissions vulnerability in SINEMA Remote Connect Server from Siemens, with a CVSS 3.1 base score of 9.9 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. The record lists versions V3.2 SP1, 3.2_sp1 as the first without the flaw, so updating SINEMA Remote Connect Server to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.47% 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
- Update SINEMA Remote Connect Server to V3.2 SP1 or 3.2_sp1, whichever matches your release line, or a later version.
- Read the advisory on cert-portal.siemens.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Siemens | SINEMA Remote Connect Server | before V3.2 SP1; before 3.2_sp1 | V3.2 SP1, 3.2_sp1 |
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
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- 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:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.3 | Critical | CNA (siemens.com) |
| CVSS 3.1 | 9.6 | Critical | CNA (siemens.com) |
| CVSS 3.1 | 9.9 | Critical | NVD |
Official description
A vulnerability has been identified in SINEMA Remote Connect Server (All versions < V3.2 SP1). The affected application does not properly assign rights to temporary files created during its update process. This could allow an authenticated attacker with the 'Manage firmware updates' role to escalate their privileges on the underlying OS level.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Creation of Temporary File With Insecure Permissions
Opening temporary files without appropriate measures or controls can leave the file, its contents and any function that it impacts vulnerable to attack.
How developers prevent this class of flaw
- Many contemporary languages have functions which properly handle this condition. Older C temp file functions are especially susceptible.
- Ensure that you use proper file permissions. This can be achieved by using a safe temp file function. Temporary files should be writable and readable only by the process that owns the file.
- Randomize temporary file names. This can also be achieved by using a safe temp-file function. This will ensure that temporary files will not be created in predictable places.
More Creation of Temporary File With Insecure Permissions vulnerabilities (CWE-378)
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 SINEMA Remote Connect Server
- 7.5 High severity
- 7.5 High severity
- 7.8 High severity
- 7.3 High severity
- 7.3 High severity
- 8.8 High severity
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