CVE-2018-18397
The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs
02 Description
The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 0.51% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 43.2% of scored records. A rank, not a probability.
- NVD base score
- 5.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- Moderate. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2018-12-12 07:00Z7 YR AGO
- Last updated
- 2024-08-05 11:08Z2 YR AGO
- Reserved
- 2018-10-16
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- Not rated by the issuing CNA
- CNA CVSS vector
- Not published by the issuing CNA
- Weaknesses
- Data version
- 5.1
- Document digest
- 1f225a648a1de8d9b4ff520c87166b387f21d3253842f7e79a74a1d1d5d3861b
05 Affected products
06 References
- usn.ubuntu.comUSN-3903-2https://usn.ubuntu.com/3903-2/
- cdn.kernel.orghttps://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.87
- github.comhttps://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1
- usn.ubuntu.comUSN-3901-2https://usn.ubuntu.com/3901-2/
- access.redhat.comRHSA-2019:0324https://access.redhat.com/errata/RHSA-2019:0324
- bugs.chromium.orghttps://bugs.chromium.org/p/project-zero/issues/detail?id=1700
- access.redhat.comRHSA-2019:0202https://access.redhat.com/errata/RHSA-2019:0202
- access.redhat.comRHSA-2019:0163https://access.redhat.com/errata/RHSA-2019:0163
- git.kernel.orghttp://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=29ec90660d68bbdd69507c1c8b4e33aa299278b1
- cdn.kernel.orghttps://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.7
- usn.ubuntu.comUSN-3901-1https://usn.ubuntu.com/3901-1/
- usn.ubuntu.comUSN-3903-1https://usn.ubuntu.com/3903-1/
- access.redhat.comRHSA-2019:0831https://access.redhat.com/errata/RHSA-2019:0831
- access.redhat.comRHBA-2019:0327https://access.redhat.com/errata/RHBA-2019:0327
07 Fixed in
Debian 12
- linux Fixed in 4.19.9-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- linux Fixed in 4.19.9-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- linux Fixed in 4.19.9-1
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 14.04 LTS
- linux-azure Fixed in 4.15.0-1040.44~14.04.1
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 16.04 LTS
- linux-aws-hwe Fixed in 4.15.0-1033.35~16.04.1
- linux-azure Fixed in 4.15.0-1040.44
- linux-gcp Fixed in 4.15.0-1028.29~16.04.1
- linux-hwe Fixed in 4.15.0-46.49~16.04.1
- linux-oracle Fixed in 4.15.0-1009.11~16.04.1
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- linux Fixed in 4.15.0-46.49
- linux-aws Fixed in 4.15.0-1033.35
- linux-azure Fixed in 4.18.0-1013.13~18.04.1
- linux-gcp Fixed in 4.15.0-1028.29
- linux-gcp-edge Fixed in 4.18.0-1007.8~18.04.1
- linux-hwe Fixed in 4.18.0-16.17~18.04.1
- linux-kvm Fixed in 4.15.0-1030.30
- linux-oem Fixed in 4.15.0-1034.39
- linux-oracle Fixed in 4.15.0-1009.11
- linux-raspi2 Fixed in 4.15.0-1032.34
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.