#VU78574 Infinite loop in Samba - CVE-2023-34966

Vulnerability identifier: #VU78574

Vulnerability risk: Medium

CVSSv4.0: 2.3 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-34966

CWE-ID: CWE-835

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Samba
Server applications / Directory software, identity management

Vendor: Samba

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to infinite loop when parsing Spotlight mdssvc RPC packets. A remote attacker can consume all available system resources and cause denial of service conditions on servers where Spotlight is explicitly enabled globally or on individual shares with "spotlight = yes".

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Samba: 4.16.0 - 4.18.4

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External links
https://access.redhat.com/security/cve/CVE-2023-34966
https://www.samba.org/samba/security/CVE-2023-34966
https://bugzilla.redhat.com/show_bug.cgi?id=2222793
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BPCSGND7LO467AJGR5DYBGZLTCGTOBCC/
https://www.zerodayinitiative.com/advisories/ZDI-23-1228/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.