CVE-2020-10994 [Medium] | Out-of-bounds Read in Pillow

CVE-2020-10994 is rated Moderate Risk (47.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.42%). Review affected assets and schedule remediation.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.44%	1.42%	+0.98%
2	2025-11-21	0.30%	0.44%	+0.14%
3	2025-11-18	—	0.30%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.44%

1.42%

+0.98%

2025-11-21

0.30%

0.44%

+0.14%

2025-11-18

—

0.30%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.5	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/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: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:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	3.6	[email protected]
4.3	2.0	MEDIUM	`AV:N/AC:M/Au:N/C:N/I:N/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:N) No confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:P) Partial availability impact.	8.6	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.5

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/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: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:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

3.6

[email protected]

4.3

2.0

MEDIUM

AV:N/AC:M/Au:N/C:N/I:N/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:N): No confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

8.6

2.9

[email protected]

OS Trackers for CVE-2020-10994

vendor	priority	summary	link
`debian`	unimportant	CVE-2020-10994 unimportant priority: Debian including 1 source packages (pillow), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2020-10994
`redhat`	low	—	https://access.redhat.com/security/cve/CVE-2020-10994
`suse`	medium	CVE-2020-10994 severity moderate: SUSE including 346 source package names (ansible-2.2.3.0-17.2, ansible-2.9.14-3.15.1, …), 575 product×package rows across 7 product lines (HPE Helion OpenStack 8, SUSE Enterprise Storage 5, … (7 product lines)): Fixed 575.	https://www.suse.com/security/cve/CVE-2020-10994/
`ubuntu`	low	CVE-2020-10994 low priority: Ubuntu including 3 source packages (pillow, pillow-python2, python-imaging), 49 status rows across 17 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 28, not-affected 13, needs-triage 3, released 3, ignored 2.	https://ubuntu.com/security/CVE-2020-10994

Affected software / configurations for CVE-2020-10994

Vendor	Product	Version	Raw CPE
python	pillow	< 7.1.0	cpe:2.3:a:python:pillow::::::::
fedoraproject	fedora	31	cpe:2.3:o:fedoraproject:fedora:31:::::::*
fedoraproject	fedora	32	cpe:2.3:o:fedoraproject:fedora:32:::::::*
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:::

References for CVE-2020-10994

URL	Tags
https://github.com/python-pillow/Pillow/commits/master/src/libImaging/	Patch Third Party Advisory
https://github.com/python-pillow/Pillow/pull/4505	Issue Tracking Patch
https://github.com/python-pillow/Pillow/pull/4538	Issue Tracking Patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BEBCPE4F2VHTIT6EZA2YZQZLPVDEBJGD/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HOKHNWV2VS5GESY7IBD237E7C6T3I427/
https://pillow.readthedocs.io/en/stable/releasenotes/	Release Notes
https://pillow.readthedocs.io/en/stable/releasenotes/7.1.0.html	Product
https://usn.ubuntu.com/4430-1/	Third Party Advisory
https://usn.ubuntu.com/4430-2/	Third Party Advisory

URL

CVE-2020-10994

Exploit prediction scoring system (EPSS) score for CVE-2020-10994

Common vulnerability scoring system (CVSS) metrics for CVE-2020-10994

Weakness enumeration for CVE-2020-10994

GitHub Security Advisory for CVE-2020-10994

OS Trackers for CVE-2020-10994

Affected software / configurations for CVE-2020-10994

References for CVE-2020-10994