CVE-2018-18955
CVE-2018-18955
Vexday Risk Score
40Attention
SSVC decision (CISA)
Attend
PoC available → attend closely
Exploit maturity
Functional exploit
Popular PoC on GitHub (23 stars) — exploitation code widely available.
CVSS —EPSS 7.6%KEV nãoPoC públicaNuclei —Metasploit simPatch referenciado
Lifecycle
15 Nov 2018Metasploit module available
16 Nov 2018Public PoC
16 Nov 2018Published on NVD
Recommendation: Plan a near-term fix — a public PoC already exists.
In the Linux kernel 4.15.x through 4.19.x before 4.19.2, map_write() in kernel/user_namespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAP_SYS_ADMIN in an affected user namespace can bypass access controls on resources outside the namespace, as demonstrated by reading /etc/shadow. This occurs because an ID transformation takes place properly for the namespaced-to-kernel direction but not for the kernel-to-namespaced direction.
Affected products
n/a · n/apublic PoCs found — 9
githubgithub.com/scheatkode/CVE-2018-18955★ 23exploitdbwww.exploit-db.com/exploits/47165unverifiedexploitdbwww.exploit-db.com/exploits/47166unverifiedexploitdbwww.exploit-db.com/exploits/47167unverifiedcve_referencewww.exploit-db.com/exploits/45915/unverifiedexploitdbwww.exploit-db.com/exploits/45886unverifiedexploitdbwww.exploit-db.com/exploits/45915unverifiedcve_referencewww.exploit-db.com/exploits/45886/unverifiedexploitdbwww.exploit-db.com/exploits/47164unverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
References
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d2f007dbe7e4c9583eea6eb04d60001e85c6f1bdhttps://bugs.chromium.org/p/project-zero/issues/detail?id=1712https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.18.19https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.2https://github.com/torvalds/linux/commit/d2f007dbe7e4c9583eea6eb04d60001e85c6f1bdhttps://security.netapp.com/advisory/ntap-20190416-0003/https://support.f5.com/csp/article/K39103040https://usn.ubuntu.com/3832-1/https://usn.ubuntu.com/3833-1/https://usn.ubuntu.com/3835-1/https://usn.ubuntu.com/3836-1/https://usn.ubuntu.com/3836-2/