CVE-2026-112902
Description
A flaw was found in Pillow. When saving an image in the TIFF format, Pillow incorrectly forwards unknown metadata tags to the underlying image processing library. A remote attacker could exploit this flaw by providing a specially crafted image containing malicious metadata to an application that processes and re-saves it. Successful exploitation allows the attacker to read out-of-bounds memory, leading to the disclosure of sensitive process memory or causing the application to crash, resulting in a Denial of Service (DoS).
Statement
This vulnerability is rated as having Important severity because it enables unauthenticated remote attackers to obtain sensitive process memory or terminate worker processes by submitting specially crafted image files. In Red Hat environments, Pillow is commonly deployed in web services and automated pipelines to process and transform user-supplied graphics. Exposure is primarily limited to application workflows that ingest untrusted images and write them out using the TIFF format, where mismatched tag handling leads to out-of-bounds reads. Successful exploitation can defeat address space layout randomization (ASLR) or disrupt image ingestion services through persistent segmentation faults.
Mitigation
To mitigate this vulnerability, apply operational controls within applications utilizing Pillow:
1. Restrict output formats: Configure image-processing workflows to avoid re-encoding or exporting untrusted user-submitted files into the TIFF format.
2. Strip metadata: If converting images to TIFF is required, strip or omit untrusted metadata, such as EXIF data or custom tags, before invoking the image save routine.
3. Process isolation: Isolate image rendering and conversion workloads within sandboxed environments or restricted containers with strict memory boundaries to limit access to sensitive memory and minimize the blast radius of worker crashes.
Caveats: Restricting image export formats or stripping metadata may alter downstream image handling and remove required tag information from generated files.
--- CME Mitigation Guidance (2026-11-04) ---
Disclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.
The highest-value action is to eliminate the forwarding of unvalidated unknown metadata tags to libtiff during TIFF encoding: upgrade to Pillow 13.0.0+ (or the corresponding fixed Red Hat builds), which stop forwarding unvalidated unknown tags to libtiff when saving TIFF images, closing all 2 injection vectors (crafted TIFF image upload, crafted EXIF metadata in JPEG, PNG, or WebP image files). Until patched, this is a concern on applications and workflows accepting untrusted image uploads and re-saving or converting them to TIFF format, so avoid re-encoding untrusted images into the TIFF format, or strip untrusted EXIF metadata and custom tags prior to invoking TIFF save routines. These controls limit blast radius and contain exploitation, but they do not fix the underlying out-of-bounds read defect — apply the upstream patch to fully remediate.
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 | 7.1 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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