Cifs-utils: local privilege escalation via forged cifs.spnego key description in cifs.upcall
cve-program · CVE-2026-12505
PublishedA flaw was found in the cifs-utils package where the cifs.upcall helper fails to securely drop its root privileges before looking up user information inside a user-controlled environment. A local, low privileged attacker can exploit this by using a crafted request_key payload to trick the root-owned helper into entering a custom environment (namespace) containing a malicious NSS module. This forces the system to load the attacker's controlled NSS Module and configuration, allowing them to execute arbitrary commands as the root user, elevating their privileges and fully compromising the system.
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cve-program · CVE-2026-12505
PublishedCifs-utils: local privilege escalation via forged cifs.spnego key description in cifs.upcall
A flaw was found in the cifs-utils package where the cifs.upcall helper fails to securely drop its root privileges before looking up user information inside a user-controlled environment. A local, low privileged attacker can exploit this by using a crafted request_key payload to trick the root-owned helper into entering a custom environment (namespace) containing a malicious NSS module. This forces the system to load the attacker's controlled NSS Module and configuration, allowing them to execute arbitrary commands as the root user, elevating their privileges and fully compromising the system.
- Source published
- 18 Jun 2026 03:34:22 UTC
- Source modified
- 4 Nov 2026 22:04:28 UTC
- Saved here
- 4 Nov 2026 23:54:02 UTC
- Source terms
- CVE Program Terms of Use
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Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 3.1 · 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H