CVE-2021-28676 — Infinite Loop in Pillow

CWE-835 — Infinite Loop11 documents8 sources
Severity
7.5HIGHNVD
OSV9.1
EPSS
0.4%
top 41.34%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
3
Python PillowFedoraproject FedoraPaloalto Pan-os
Timeline
PublishedJun 2
Latest updateMar 31

Description

An issue was discovered in Pillow before 8.2.0. For FLI data, FliDecode did not properly check that the block advance was non-zero, potentially leading to an infinite loop on load.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 3.9 | Impact: 3.6

Affected Packages5 packages

▶NVDpython/pillow< 8.2.0
▶PyPIpython/pillow< 8.2.0
▶Debianpython/pillow< 8.1.2+dfsg-0.2+3
▶Ubuntupython/pillow< 2.3.0-1ubuntu3.4+esm5+2
▶Palo Altopaloalto/pan-os

Also affects: Fedora 33

Patches

Patch: github.com ↗Patch: github.com ↗

🔴Vulnerability Details

5
OSV
pillow vulnerabilities↗2026-03-31
▶
OSV
Potential infinite loop in Pillow↗2021-06-08
▶
GHSA
Potential infinite loop in Pillow↗2021-06-08
▶
OSV
CVE-2021-28676: An issue was discovered in Pillow before 8↗2021-06-02
▶
CVEList
CVE-2021-28676: An issue was discovered in Pillow before 8↗2021-06-02
▶

📋Vendor Advisories

5
Ubuntu
Pillow vulnerabilities↗2026-03-31
▶
Palo Alto
PAN-SA-2024-0001 Informational Bulletin: Impact of OSS CVEs in PAN-OS↗2024-02-14
▶
Ubuntu
Pillow vulnerabilities↗2021-05-19
▶
Red Hat
python-pillow: Infinite loop in FLI image reader↗2021-04-01
▶
Debian
CVE-2021-28676: pillow - An issue was discovered in Pillow before 8.2.0. For FLI data, FliDecode did not ...↗2021
▶
CVE-2021-28676 — Infinite Loop in Python Pillow | cvebase