Kernel: ksmbd brute force delay bypass via asynchronous requests
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-307.
Summary
A vulnerability has been identified in the Linux kernel's ksmbd component (kernel SMB/CIFS server). A security control designed to prevent dictionary attacks, which introduces a 5-second delay during session setup, can be bypassed through the use of asynchronous requests. This bypass negates the intended anti-brute-force protection, potentially allowing attackers to conduct dictionary attacks more efficiently against user credentials or other authentication mechanisms.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | linux | before 5.15.145; 6.0.0 and later; 6.1.0 to before 6.1.29; 6.2.0 to before 6.2.16; 6.3.0 to before 6.3.2 | 5.15.145, 6.1.29, 6.2.16, 6.3.2 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 10 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | Not affected | CNA |
- linux Vendor— Affected before 5.15.145; 6.0.0 and later; 6.1.0 to before 6.1.29; 6.2.0 to before 6.2.16; 6.3.0 to before 6.3.2 Fixed in 5.15.145, 6.1.29, 6.2.16, 6.3.2 Patch available CNA
- Red Hat Enterprise Linux 10 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — Not affected CNA
Remediation
- Fix · CNA linux Fixed in 5.15.145, 6.1.29, 6.2.16, 6.3.2
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
Not affected: 5 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2023-32251
- 2026-10-03 Alias added: GHSA-7rf9-h4hc-6359
References
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Sources
- CVE-2023-32251 · CVE Program
- CVE-2023-32251 · NVD
- FIRST EPSS
- GHSA-7rf9-h4hc-6359 · GitHub Advisory Database · CC BY 4.0
- CVE-2023-32251 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences