Snapdragon: Out-of-bounds Write
CVE-2025-21468 is a high-severity out-of-bounds write vulnerability in Snapdragon from Qualcomm, 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. Affected Snapdragon versions: AR8035; CSRA6620; CSRA6640, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.11% 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
- Check which version of Snapdragon you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on docs.qualcomm.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Qualcomm | Snapdragon | AR8035; CSRA6620; CSRA6640; FastConnect 6200; FastConnect 6700; FastConnect 6900; FastConnect 7800; Flight RB5 5G Platform; and 32 more ranges | Not stated |
| Qualcomm | Ar8035 Firmware | Not specified in the record | Not stated |
| Qualcomm | Csra6620 Firmware | Not specified in the record | Not stated |
| Qualcomm | Csra6640 Firmware | Not specified in the record | Not stated |
| Qualcomm | Fastconnect 6200 Firmware | Not specified in the record | Not stated |
| Qualcomm | Fastconnect 6700 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcd9380 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcd9385 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcd9390 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcd9395 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn3910 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn3950 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn3980 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn3988 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn3990 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn6450 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn6650 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn6740 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn6755 Firmware | Not specified in the record | Not stated |
| Qualcomm | Wcn7750 Firmware | Not specified in the record | Not stated |
| Qualcomm | Qca6595 Firmware | Not specified in the record | Not stated |
| Qualcomm | Qca6595au Firmware | Not specified in the record | Not stated |
| Qualcomm | Qca6696 Firmware | Not specified in the record | Not stated |
| Qualcomm | Qca6698aq Firmware | Not specified in the record | Not stated |
| Qualcomm | Qca8081 Firmware | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE; 35 further products are omitted here. 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 CNA (qualcomm.com).
Official description
Memory corruption while reading response from FW, when buffer size is changed by FW while driver is using this size to write null character at the end of buffer.
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.
- 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 Snapdragon
- 7.1 High severity
- 7.0 High severity
Recent Out-of-bounds Write vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.8 High severity
- 7.8 High severity
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