SIMATIC S7-1500 TM MFP - GNU/Linux subsystem: Use After Free
CVE-2022-32250 is a high-severity use after free vulnerability in SIMATIC S7-1500 TM MFP - GNU/Linux subsystem from Siemens, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version V1.1 as the first without the flaw, so updating SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 2.91% chance of exploitation within 30 days, higher than 87% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to V1.1 or a later version.
- Update Linux Kernel to 4.9.318 or 4.14.283 or 4.19.247 or 5.4.198, whichever matches your release line, or a later version.
- Read the advisory on git.kernel.org for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Siemens | SIMATIC S7-1500 TM MFP - GNU/Linux subsystem | before V1.1 | V1.1 |
| Linux | Linux Kernel | 4.1 up to, but not including, 4.9.318; 4.10 up to, but not including, 4.14.283; 4.15 up to, but not including, 4.19.247; 4.20 up to, but not including, 5.4.198; 5.5 up to, but not including, 5.10.120; 5.11 up to, but not including, 5.15.45; 5.16 up to, but not including, 5.17.13; 5.18 up to, but not including, 5.18.2 | 4.9.318, 4.14.283, 4.19.247, 5.4.198, 5.10.120, 5.15.45 |
| Fedora Project | Fedora | 35; 36 | Not stated |
| Debian | Debian Linux | 9.0; 10.0 | Not stated |
| NetApp | H300s Firmware | Not specified in the record | Not stated |
| NetApp | H500s Firmware | Not specified in the record | Not stated |
| NetApp | H700s Firmware | Not specified in the record | Not stated |
| NetApp | H410s Firmware | Not specified in the record | Not stated |
| NetApp | H410c Firmware | Not specified in the record | 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
- LocalThe attacker needs local access or must trick a user into running something.
- 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
- 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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | NVD |
| CVSS 2.0 | 7.2 | High | NVD |
Official description
net/netfilter/nf_tables_api.c in the Linux kernel through 5.18.1 allows a local user (able to create user/net namespaces) to escalate privileges to root because an incorrect NFT_STATEFUL_EXPR check leads to a use-after-free.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
- openwall.com/lists/oss-security/2022/06/03/1Exploit, Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2022/06/04/1Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2022/08/25/1Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2022/05/31/1Exploit, Mailing List, Third Party Advisory
Third-party and government advisories
- openwall.com/lists/oss-security/2022/06/20/1Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2022/07/03/5Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2022/07/03/6Mailing List, Third Party Advisory
- openwall.com/lists/oss-security/2022/09/02/9Mailing List, Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2092427Issue Tracking, Third Party Advisory
- lists.debian.org/debian-lts-announce/2022/07/msg00000.htmlMailing List, Third Party Advisory
- security.netapp.com/advisory/ntap-20220715-0005/Third Party Advisory
- debian.org/security/2022/dsa-5161Third Party Advisory
- debian.org/security/2022/dsa-5173Third Party Advisory
Technical write-ups (may include proof of concept)
- blog.theori.io/research/CVE-2022-32250-linux-kernel-lpe-2022/Exploit, Third Party Advisory
- github.com/theori-io/CVE-2022-32250-exploitExploit, Third Party Advisory
Other references
Other vulnerabilities in SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
- 7.8 High severity
- 7.8 High severity
Linux Kernel Unspecified Exploited
- 8.8 High severity
- 7.8 High severity
- 8.8 High severity
- 8.2 High severity
Recent Use After Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
Spotted an error? Tell us.