Lifebook A3510 Firmware: Out-of-bounds Write
CVE-2022-28806 is a high-severity out-of-bounds write vulnerability in Lifebook A3510 Firmware from Fujitsu, 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 1.09 as the first without the flaw, so updating Lifebook A3510 Firmware to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.48% 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 Lifebook A3510 Firmware to 1.09 or a later version.
- Update Lifebook U9310 Firmware to 2.17 or a later version.
- Update Lifebook U7511 Firmware to 2.30 or a later version.
- Read the advisory on fmworld.net for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Fujitsu | Lifebook A3510 Firmware | before 1.09 | 1.09 |
| Fujitsu | Lifebook U9310 Firmware | before 2.17 | 2.17 |
| Fujitsu | Lifebook U7511 Firmware | before 2.30 | 2.30 |
| Fujitsu | Lifebook U7411 Firmware | before 2.30 | 2.30 |
| Fujitsu | Lifebook U7311 Firmware | before 2.30 | 2.30 |
| Fujitsu | Lifebook U9311 Firmware | 2.33 and earlier | Not stated |
| Fujitsu | Lifebook E5510 Firmware | before 2.23 | 2.23 |
| Fujitsu | Lifebook U7510 Firmware | before 2.19 | 2.19 |
| Fujitsu | Lifebook U7410 Firmware | before 2.19 | 2.19 |
| Fujitsu | Lifebook U7310 Firmware | before 2.13 | 2.13 |
| Fujitsu | Lifebook E459 Firmware | before 1.09 | 1.09 |
| Fujitsu | Lifebook E449 Firmware | before 1.09 | 1.09 |
Version data comes from NVD's product matching. 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
An issue was discovered on certain Fujitsu LIEFBOOK devices (A3510, U9310, U7511/U7411/U7311, U9311, E5510/E5410, U7510/U7410/U7310, E459/E449) with BIOS versions before v1.09 (A3510), v2.17 (U9310), v2.30 (U7511/U7411/U7311), v2.33 (U9311), v2.23 (E5510), v2.19 (U7510/U7410), v2.13 (U7310), and v1.09 (E459/E449). The FjGabiFlashCoreAbstractionSmm driver registers a Software System Management Interrupt (SWSMI) handler that is not sufficiently validated to ensure that the CommBuffer (or any other communication buffer's nested contents) are not pointing to SMRAM contents. A potential attacker can therefore write fixed data to SMRAM, which could lead to data corruption inside this memory (e.g., change the SMI handler's code or modify SMRAM map structures to break input pointer validation for other SMI handlers). Thus, the attacker could elevate privileges from ring 0 to ring -2 and execute arbitrary code in SMM.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Write
The product writes data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Third-party and government advisories
- kb.cert.org/vuls/id/796611Third Party Advisory, US Government Resource
Technical write-ups (may include proof of concept)
- binarly.io/advisoriesExploit, Third Party Advisory
Other references
Recent Out-of-bounds Write vulnerabilities
- 7.2 High severity
- 7.5 High severity
- 7.2 High severity
- 7.8 High severity
- 7.8 High severity
- 9.8 Critical severity
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