CVE-2021-28678

An issue was discovered in Pillow before 8.2.0. For BLP data, BlpImagePlugin did not properly check that reads (after jumping to file offsets) returned data. This could lead to a DoS where the decoder could be run a large number of times on empty data.

Published: 2021-06-02 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-28678 is rated Moderate Risk (40/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.73%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-28678

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.08% 0.73% +0.65%
2 2025-06-21 0.21% 0.08% -0.13%
3 2025-06-19 — 0.21% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-28678

CVSS metrics for this CVE.

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]

Weakness enumeration for CVE-2021-28678

GitHub Security Advisory for CVE-2021-28678

GHSA-hjfx-8p6c-g7gx · Severity: medium · Ecosystem: pip — Insufficient Verification of Data Authenticity in Pillow

OS Trackers for CVE-2021-28678

vendor priority summary link
alpine medium CVE-2021-28678: 1 source package rows (py3-pillow); 8 state rows across 8 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community, edge-main); fixed 8, open 0. https://security.alpinelinux.org/vuln/CVE-2021-28678
debian not yet assigned CVE-2021-28678 not yet assigned 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-2021-28678
gentoo normal CVE-2021-28678: 1 GLSA(s) (202107-33), 1 atom(s) (dev-python/pillow); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-28678
redhat medium — https://access.redhat.com/security/cve/CVE-2021-28678
suse high CVE-2021-28678 severity important: SUSE including 7 source package names (python-Pillow, python-Pillow-5.2.0-3.8.1, …), 33 product×package rows across 17 product lines (HPE Helion OpenStack 8, SUSE Liberty Linux 8, … (17 product lines)): Known Not Affected 25, Fixed 8. https://www.suse.com/security/cve/CVE-2021-28678/
ubuntu low CVE-2021-28678 low priority: Ubuntu including 3 source packages (pillow, pillow-python2, python-imaging), 48 status rows across 16 suites (bionic, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 28, released 14, ignored 2, needs-triage 2, not-affected 2. https://ubuntu.com/security/CVE-2021-28678

Affected software / configurations for CVE-2021-28678

Vendor Product Version Raw CPE
python pillow < 8.2.0 cpe:2.3:a:python:pillow:*:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*

References for CVE-2021-28678

cvelogic Threat Intelligence