Secuno
ENNL
Book demo

CVE-2026-28231

Bigcat88 Pillow-heif out-of-bounds read

9.1 CRITICALPublic exploitEPSS 0.71%
  1. Published27 Feb 2026

Description

pillow_heif is a Python library for working with HEIF images and plugin for Pillow. Prior to version 1.3.0, an integer overflow in the encode path buffer validation of `_pillow_heif.c` allows an attacker to bypass bounds checks by providing large image dimensions, resulting in a heap out-of-bounds read. This can lead to information disclosure (server heap memory leaking into encoded images) or denial of service (process crash). No special configuration is required — this triggers under default settings. Version 1.3.0 fixes the issue.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Affected products

Bigcat88 Pillow-heif< 1.3.0

Remediation

Fixed in
Bigcat88 Pillow-heif≥ 1.3.0

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-9722910.0
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 19.2 before…
CVE-2026-1078378.2
RIOT is an open-source microcontroller operating system designed for Internet of Things…
CVE-2026-195698.8
dynamic_object_create() in kernel/userspace/userspace.c computed the backing allocation…
CVE-2026-78269.1
A heap-based out-of-bounds read in the BufferSerializerIOv2_ReadBuffer function…
CVE-2026-823348.1
IBM Guardium Data Protection 12.0, 12.1, 12.2 is vulnerable to a heap-based…
CVE-2026-144968.2
IBM DataPower Gateway 10.5.0.0 through 10.5.0.22, 10.6.1 through 10.6.6, 10.6.0.0…

Frequently asked

Is CVE-2026-28231 being actively exploited?

CVE-2026-28231 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.71%.

How severe is CVE-2026-28231?

CVE-2026-28231 has a CVSS 3.1 base score of 9.1, rated critical. EPSS estimates a 0.71% probability of exploitation.

Which products are affected by CVE-2026-28231?

Affected products include Bigcat88 Pillow-heif.

How do I fix CVE-2026-28231?

Upgrade affected software to a fixed version, for example Bigcat88 Pillow-heif 1.3.0 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-28231 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.