Buffer overflow in GNU Grub2
CVE-2020-14311
There is an issue with grub2 before version 2.06 while handling symlink on ext filesystems. A filesystem containing a symbolic link with an inode size of UINT32_MAX causes an arithmetic overflow leading to a zero-sized memory allocation with subsequent heap-based buffer overflow.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (37.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 37.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- GNU Grub2
- The Grub2 Project — versions 2.06
- Canonical Ubuntu Linux — versions 14.04, 16.04, 18.04
- openSUSE Leap — versions 15.1, 15.2
- Red Hat Enterprise Linux — versions 7.0, 8.0
- Red Hat Enterprise Linux Eus — versions 8.1, 8.2
- Red Hat Enterprise Linux Server Aus — versions 8.2
- Red Hat Enterprise Linux Server Tus — versions 8.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
- usn.ubuntu.com/4432-1/ (vendor-advisory, Third Party Advisory)
- lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html (vendor-advisory, Mailing List, Third Party Advisory)
- lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html (vendor-advisory, Mailing List, Third Party Advisory)
- security.gentoo.org/glsa/202104-05 (vendor-advisory, Third Party Advisory)
- www.openwall.com/lists/oss-security/2021/09/17/2 (mailing-list, Mailing List, Third Party Advisory)
- www.openwall.com/lists/oss-security/2021/09/17/4 (mailing-list, Mailing List, Third Party Advisory)
- www.openwall.com/lists/oss-security/2021/09/21/1 (mailing-list, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-14311?
- CVE-2020-14311 is a medium-severity vulnerability in GNU Grub2, classified under Heap-based Buffer Overflow. CVSS score: 5.7/10. Published 2020-07-31.
- How severe is CVE-2020-14311?
- Medium severity. CVSS v3 base score is 5.7 out of 10.
- Is CVE-2020-14311 known to be exploited?
- 27 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.