Path Traversal in Linux Kernel
CVE-2021-3178
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
Vulnerability class: Path Traversal (Directory Traversal)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.024 (83.6th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 83.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.024 · newest: 0.024 · change: 0.000
Affected products
- Linux Kernel
- Debian Linux — versions 9.0
- Fedoraproject Fedora — versions 33
Weakness classification (CWE)
Public proof-of-concept exploits
References
- patchwork.kernel.org/project/linux-nfs/patch/20210111210129.GA11652@fieldses.or…
- git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/ (Patch, Mailing List, Vendor Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.debian.org/debian-lts-announce/2021/03/msg00010.html (mailing-list, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-3178?
- CVE-2021-3178 is a medium-severity vulnerability in Linux Kernel, classified under Path Traversal. CVSS score: 6.5/10. Published 2021-01-19.
- How severe is CVE-2021-3178?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2021-3178 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.