Vulnerability · Published Dec 2, 2020 · Assigned by redhat
CVE-2020-25656
Medium 4.1
In plain English
A medium-severity use-after-free in kernel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 38% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)4.1Medium
Exploit odds (30 days)0.4%top 61.6% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
A flaw was found in the Linux kernel. A use-after-free was found in the way the console subsystem was using ioctls KDGKBSENT and KDSKBSENT. A local user could use this flaw to get read memory access out of bounds. The highest threat from this vulnerability is to data confidentiality.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | bpftool | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-abi-stablelists | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-core | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-cross-headers | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-debug | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-debug-core | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-debug-devel | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-debug-modules | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-debug-modules-extra | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-devel | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-doc | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-headers | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-modules | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-modules-extra | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-rt | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-core | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-debug | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-debug-core | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-debug-devel | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-debug-kvm | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-debug-modules | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-debug-modules-extra | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-devel | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-kvm | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-modules | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-rt-modules-extra | 4.18.0-553.rt7.342.el8_10 | ALSA-2024:2950 |
| AlmaLinux:8 | kernel-tools | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-tools-libs | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-tools-libs-devel | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-zfcpdump | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-zfcpdump-core | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-zfcpdump-devel | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-zfcpdump-modules | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | kernel-zfcpdump-modules-extra | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | perf | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| AlmaLinux:8 | python3-perf | 4.18.0-553.el8_10 | ALSA-2024:3138 |
| Debian:12 | linux | 5.9.6-1 | DEBIAN-CVE-2020-25656 |
| Debian:13 | linux | 5.9.6-1 | DEBIAN-CVE-2020-25656 |
| Debian:14 | linux | 5.9.6-1 | DEBIAN-CVE-2020-25656 |
| Rocky Linux:8 | kernel | 0:4.18.0-553.el8_10 | RLSA-2024:3138 |
| Rocky Linux:8 | kernel | 0:4.18.0-553.123.1.el8_10.cloud.0.1 | RXSA-2024:3138 |
| Rocky Linux:8 | kernel-rt | 0:4.18.0-553.rt7.342.el8_10 | RLSA-2024:2950 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2020-25656 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2020-25656 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2020-25656 |
Affected products (as reported)
Weakness: CWE-416
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1888726
- https://lkml.org/lkml/2020/10/29/528
- https://lkml.org/lkml/2020/10/16/84
- [debian-lts-announce] 20201210 [SECURITY] [DLA 2483-1] linux-4.19 security update mailing-list
- [debian-lts-announce] 20201218 [SECURITY] [DLA 2494-1] linux security update mailing-list
- https://www.starwindsoftware.com/security/sw-20210325-0006/