CVE-2026-96638
Description
A flaw was found in Pillow. When processing run-length encoded (RLE) bitmap images, the decoder fails to properly limit memory allocation for certain escape sequences and data runs. A remote attacker could exploit this flaw by supplying a specially crafted BMP image file to an application, causing excessive memory consumption and resulting in a Denial of Service (DoS).
Statement
Red Hat rates this vulnerability as Moderate impact because exploitation is constrained to a denial of service via memory exhaustion, with no compromise to system confidentiality or integrity. Within Red Hat environments, Pillow is included as a supporting library across containerized platforms and automation tooling, where triggering the flaw requires an application to ingest and decode untrusted bitmap files. Systems and services that do not process untrusted image uploads or run-length encoded graphics are not exposed to this risk.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | N/A | 6.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Amplification; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)
System resources, CPU and memory, can be quickly consumed. This can lead to poor system performance or system crash.
Frequently Asked Questions
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