What is CVE-2020-5312?

CVE-2020-5312 is a critical-severity vulnerability in Python Pillow, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2020-01-03.

How severe is CVE-2020-5312?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2020-5312 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Python Pillow

CVE-2020-5312

libImaging/PcxDecode.c in Pillow before 6.2.2 has a PCX P mode buffer overflow.

Vulnerability class: Buffer Overflow

Published 2020-01-03 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.037 (89.3th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 89.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.037 · newest: 0.037 · change: 0.000

Affected products

Python Pillow
Canonical Ubuntu Linux — versions 14.04, 16.04, 18.04
Debian Linux — versions 9.0, 10.0
Fedoraproject Fedora — versions 30, 31

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

Public proof-of-concept exploits

suchithrzp/test-sca

References

pillow.readthedocs.io/en/stable/releasenotes/6.2.2.html (Third Party Advisory, Release Notes)
github.com/python-pillow/Pillow/commit/93b22b846e0269ee9594ff71a72bec02d2bea8fd (Patch, Third Party Advisory)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
usn.ubuntu.com/4272-1/ (vendor-advisory, Third Party Advisory)
access.redhat.com/errata/RHSA-2020:0566 (vendor-advisory, Third Party Advisory)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
www.debian.org/security/2020/dsa-4631 (vendor-advisory, Third Party Advisory)
access.redhat.com/errata/RHSA-2020:0580 (vendor-advisory, Third Party Advisory)
access.redhat.com/errata/RHSA-2020:0578 (vendor-advisory, Third Party Advisory)
access.redhat.com/errata/RHSA-2020:0681 (vendor-advisory, Third Party Advisory)

Frequently asked questions

What is CVE-2020-5312?: CVE-2020-5312 is a critical-severity vulnerability in Python Pillow, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2020-01-03.
How severe is CVE-2020-5312?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2020-5312 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.