Vulnerability · Published Jan 19, 2021 · Assigned by mitre
CVE-2021-3178
Medium 6.5
In plain English
A medium-severity security flaw in the linux package (Debian). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.4% (higher than 84% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)6.5Medium
Exploit odds (30 days)2.4%top 15.6% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
fs/nfsd/nfs3xdr.c in the Linux kernel through 5.10.8, when there is an NFS export of a subdirectory of a filesystem, allows remote attackers to traverse to other parts of the filesystem via READDIRPLUS. NOTE: some parties argue that such a subdirectory export is not intended to prevent this attack; see also the exports(5) no_subtree_check default behavior
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | 5.10.12-1 | DEBIAN-CVE-2021-3178 |
| Debian:13 | linux | 5.10.12-1 | DEBIAN-CVE-2021-3178 |
| Debian:14 | linux | 5.10.12-1 | DEBIAN-CVE-2021-3178 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2021-3178 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2021-3178 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2021-3178 |
Affected products (as reported)
References
- https://patchwork.kernel.org/project/linux-nfs/patch/20210111210129.GA11652%40fieldses.org/ x_refsource_MISC
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=51b2ee7d006a736a9126e8111d1f24e4fd0afaa6 x_refsource_MISC
- FEDORA-2021-3bcc7198c8 vendor-advisory, x_refsource_FEDORA
- [debian-lts-announce] 20210309 [SECURITY] [DLA 2586-1] linux security update mailing-list, x_refsource_MLIST