Buffer overflow in GNU Grub2
CVE-2021-3697
A crafted JPEG image may lead the JPEG reader to underflow its data pointer, allowing user-controlled data to be written in heap. To a successful to be performed the attacker needs to perform some triage over the heap layout and craft an image with a malicious format and payload. This vulnerability can lead to data corruption and eventual code execution or secure boot circumvention. This flaw affects grub2 versions prior grub-2.12.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (38.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 38.3% 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
- Red Hat Codeready Linux Builder
- Red Hat Developer Tools — versions 1.0
- Red Hat Enterprise Linux — versions 8.0, 8.1, 8.4
- Red Hat Enterprise Linux Eus — versions 8.2, 8.4, 8.6
- Red Hat Enterprise Linux For Power Little Endian — versions 8.0, 9.0
- Red Hat Enterprise Linux For Power Little Endian Eus — versions 8.2, 8.4, 8.6
- Red Hat Enterprise Linux Server Aus — versions 8.2, 8.4, 8.6
- Red Hat Enterprise Linux Server For Power Little Endian Update Services SAP Solutions — versions 8.1, 8.2, 8.4
- Red Hat Enterprise Linux Server Tus — versions 8.2, 8.4, 8.6
Weakness classification (CWE)
Public proof-of-concept exploits
References
- bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
- security.gentoo.org/glsa/202209-12 (vendor-advisory, Third Party Advisory)
- security.netapp.com/advisory/ntap-20220930-0001/ (Third Party Advisory)
Frequently asked questions
- What is CVE-2021-3697?
- CVE-2021-3697 is a high-severity vulnerability in GNU Grub2, classified under Out-of-bounds Write. CVSS score: 7.0/10. Published 2022-07-06.
- How severe is CVE-2021-3697?
- High severity. CVSS v3 base score is 7.0 out of 10.
- Is CVE-2021-3697 known to be exploited?
- 19 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.