Quick answers
- Is CVE-2026-3238 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-3238 being exploited in the wild.
- How severe is CVE-2026-3238?
- High severity, with a CVSS score of 7.5, published 8 June 2026.
- Which products and versions are affected?
- Samba All versions since 4.0 before 4.22.10, 4.23.8, 4.24.3.
- Is there a fix for CVE-2026-3238?
- A patch was published on 2026-06-08. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-3238 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-3238?
- Check whether you run Samba at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A NULL pointer dereference vulnerability exists in Samba's WINS server component when configured as an Active Directory Domain Controller. The flaw is located in the protocol handlers for RELEASE and MULTI_HOME_REG packets, which fail to properly validate incoming requests. An unauthenticated remote attacker can exploit this by sending specially crafted UDP packets to the WINS service, triggering a crash. While the service may restart, the ease of exploitation allows for a sustained denial-of-service state. This vulnerability only affects installations where 'wins support = yes' is explicitly enabled in the smb.conf file. Patches are available in versions 4.22.10, 4.23.8, and 4.24.3.
Affected products
- Samba Samba All versions since 4.0 before 4.22.10, 4.23.8, 4.24.3
Timeline
- 2026-06-08: disclosed
- 2026-06-08: advisory
- 2026-06-08: patched