CVE-2020-14310 [Medium] | Memory Corruption in Grub2

There is an issue on grub2 before version 2.06 at function read_section_as_string(). It expects a font name to be at max UINT32_MAX - 1 length in bytes but it doesn't verify it before proceed with buffer allocation to read the value from the font value. An attacker may leverage that by crafting a malicious font file which has a name with UINT32_MAX, leading to read_section_as_string() to an arithmetic overflow, zero-sized allocation and further heap-based buffer overflow.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.05%	0.48%	+0.43%
2	2025-10-20	0.05%	0.05%	+0.00%
3	2025-10-02	—	0.05%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.05%

0.48%

+0.43%

2025-10-20

0.05%

+0.00%

2025-10-02

—

0.05%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.7	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:H) They need powerful rights—admin, root, or similar—before this pays off. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.5	5.2	[email protected]
6.0	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:H) They need powerful rights—admin, root, or similar—before this pays off. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	0.8	5.2	[email protected]
3.6	2.0	LOW	`AV:L/AC:L/Au:N/C:N/I:P/A:P` Click to expand Access vector (AV:L) Requires local access to the target system. Access complexity (AC:L) Exploitation conditions are straightforward and predictable. Authentication (AU:N) No authentication is required. Confidentiality impact (C:N) No confidentiality impact. Integrity impact (I:P) Partial integrity impact. Availability impact (A:P) Partial availability impact.	3.9	4.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.7

3.1

MEDIUM

CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H): They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.5

5.2

[email protected]

6.0

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H): They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

0.8

5.2

[email protected]

3.6

2.0

LOW

AV:L/AC:L/Au:N/C:N/I:P/A:P Click to expand

Access vector (AV:L): Requires local access to the target system.
Access complexity (AC:L): Exploitation conditions are straightforward and predictable.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:N): No confidentiality impact.
Integrity impact (I:P): Partial integrity impact.
Availability impact (A:P): Partial availability impact.

3.9

4.9

[email protected]

OS Trackers for CVE-2020-14310

vendor	priority	summary	link
`alpine`	medium	CVE-2020-14310: 1 source package rows (grub); 7 state rows across 7 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 7, open 0.	https://security.alpinelinux.org/vuln/CVE-2020-14310
`debian`	not yet assigned	CVE-2020-14310 not yet assigned priority: Debian including 1 source packages (grub2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2020-14310
`gentoo`	normal	CVE-2020-14310: 1 GLSA(s) (202104-05), 1 atom(s) (sys-devel/grub); latest impact normal.	https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-14310
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2020-14310
`suse`	medium	CVE-2020-14310 severity moderate: SUSE including 200 source package names (grub2-2.02-12.31.1, grub2-2.02-19.48.1, …), 432 product×package rows across 75 product lines (HPE Helion OpenStack 8, Image SLES12-SP5-Azure-BYOS, … (75 product lines)): Fixed 432.	https://www.suse.com/security/cve/CVE-2020-14310/
`ubuntu`	high	CVE-2020-14310 high priority: Ubuntu including 3 source packages (grub2, grub2-signed, grub2-unsigned), 44 status rows across 16 suites (bionic, eoan, focal, groovy, hirsute, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 28, released 10, needs-triage 3, DNE 1, ignored 1, needed 1.	https://ubuntu.com/security/CVE-2020-14310

Affected software / configurations for CVE-2020-14310

Vendor	Product	Version	Raw CPE
gnu	grub2	< 2.06	cpe:2.3:a:gnu:grub2::::::::
redhat	enterprise_linux	7.0	cpe:2.3:o:redhat:enterprise_linux:7.0:::::::*
redhat	enterprise_linux	8.0	cpe:2.3:o:redhat:enterprise_linux:8.0:::::::*
redhat	enterprise_linux_eus	8.1	cpe:2.3:o:redhat:enterprise_linux_eus:8.1:::::::*
redhat	enterprise_linux_eus	8.2	cpe:2.3:o:redhat:enterprise_linux_eus:8.2:::::::*
redhat	enterprise_linux_server_aus	8.2	cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:::::::*
redhat	enterprise_linux_server_tus	8.2	cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:::::::*
opensuse	leap	15.1	cpe:2.3:o:opensuse:leap:15.1:::::::*
opensuse	leap	15.2	cpe:2.3:o:opensuse:leap:15.2:::::::*
canonical	ubuntu_linux	14.04	cpe:2.3:o:canonical:ubuntu_linux:14.04::::esm:::
canonical	ubuntu_linux	16.04	cpe:2.3:o:canonical:ubuntu_linux:16.04::::esm:::
canonical	ubuntu_linux	18.04	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::
canonical	ubuntu_linux	20.04	cpe:2.3:o:canonical:ubuntu_linux:20.04::::lts:::

References for CVE-2020-14310

URL	Tags
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00016.html	Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00017.html	Mailing List Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-14310	Issue Tracking Vendor Advisory
https://security.gentoo.org/glsa/202104-05	Third Party Advisory
https://usn.ubuntu.com/4432-1/	Third Party Advisory

URL

CVE-2020-14310

Exploit prediction scoring system (EPSS) score for CVE-2020-14310

Common vulnerability scoring system (CVSS) metrics for CVE-2020-14310

Weakness enumeration for CVE-2020-14310

OS Trackers for CVE-2020-14310

Affected software / configurations for CVE-2020-14310

References for CVE-2020-14310