Vulnerability · Published May 26, 2021 · Assigned by redhat
CVE-2021-20177
Medium 4.4
In plain English
A medium-severity out-of-bounds read in kernel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)4.4Medium
Exploit odds (30 days)0.3%top 79.1% 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's implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) when inserting iptables rules could insert a rule which can panic the system. Kernel before kernel 5.5-rc1 is affected.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 5.5.13-1 | DEBIAN-CVE-2021-20177 |
| Debian:13 | linux | 5.5.13-1 | DEBIAN-CVE-2021-20177 |
| Debian:14 | linux | 5.5.13-1 | DEBIAN-CVE-2021-20177 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2021-20177 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2021-20177 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2021-20177 |
Affected products (as reported)
Weakness: CWE-125
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1914719 x_refsource_MISC