CVE-2020-5496 [High] | Out-of-bounds Write in Fontforge

CVE-2020-5496 is rated High Exploit Risk (64.8/100): CVSS High severity, with low exploitation likelihood (EPSS 0.20%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

EDB-ID	Source	Kind	Published	Link
—	nvd_ref	exploit_tag		Exploit-DB ↗

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#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-11-21	0.52%	0.20%	-0.31%
2	2025-11-18	0.20%	0.52%	+0.31%
3	2025-04-27	—	0.20%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-11-21

0.52%

0.20%

-0.31%

2025-11-18

0.20%

0.52%

+0.31%

2025-04-27

—

0.20%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.8	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. 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:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big 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.	2.8	5.9	[email protected]
6.8	2.0	MEDIUM	`AV:N/AC:M/Au:N/C:P/I:P/A:P` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:M) Exploitation needs some favorable conditions, but not exceptional ones. Authentication (AU:N) No authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:P) Partial integrity impact. Availability impact (A:P) Partial availability impact.	8.6	6.4	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.8

3.1

HIGH

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

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big 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.

2.8

5.9

[email protected]

6.8

2.0

MEDIUM

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

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:M): Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:P): Partial integrity impact.
Availability impact (A:P): Partial availability impact.

8.6

6.4

[email protected]

OS Trackers for CVE-2020-5496

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2020-5496 not yet assigned priority: Debian including 1 source packages (fontforge), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2020-5496
`gentoo`	normal	CVE-2020-5496: 1 GLSA(s) (202004-14), 1 atom(s) (media-gfx/fontforge); latest impact normal.	https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2020-5496
`redhat`	low	—	https://access.redhat.com/security/cve/CVE-2020-5496
`suse`	medium	CVE-2020-5496 severity moderate: SUSE including 12 source package names (fontforge, fontforge-20170731-11.11.1, …), 15 product×package rows across 10 product lines (SUSE Linux Enterprise Module for Desktop Applications 15 SP2, SUSE Linux Enterprise Module for Desktop Applications 15 SP3, … (10 product lines)): Fixed 14, Known Not Affected 1.	https://www.suse.com/security/cve/CVE-2020-5496/
`ubuntu`	medium	CVE-2020-5496 medium priority: Ubuntu including 1 source packages (fontforge), 18 status rows across 18 suites (bionic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 10, needs-triage 4, ignored 3, DNE 1.	https://ubuntu.com/security/CVE-2020-5496

Affected software / configurations for CVE-2020-5496

Vendor	Product	Version	Raw CPE
fontforge	fontforge	20190801	cpe:2.3:a:fontforge:fontforge:20190801:::::::*
opensuse	leap	15.1	cpe:2.3:o:opensuse:leap:15.1:::::::*

References for CVE-2020-5496

URL	Tags
http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00041.html	Third Party Advisory
https://github.com/fontforge/fontforge/issues/4085	Exploit Issue Tracking Third Party Advisory
https://lists.debian.org/debian-lts-announce/2024/03/msg00007.html
https://security.gentoo.org/glsa/202004-14	Third Party Advisory

URL

CVE-2020-5496

Public exploit references (Exploit-DB) for CVE-2020-5496

Exploit prediction scoring system (EPSS) score for CVE-2020-5496

Common vulnerability scoring system (CVSS) metrics for CVE-2020-5496

Weakness enumeration for CVE-2020-5496

OS Trackers for CVE-2020-5496

Affected software / configurations for CVE-2020-5496

References for CVE-2020-5496