CVE-2026-47318: Samsung rlottie Buffer Overflow Flaw

CVE-2026-47318 Overview

CVE-2026-47318 is a stack-based buffer overflow [CWE-121] in Samsung Open Source rlottie, a library that renders Lottie animations parsed from JSON. The flaw affects all rlottie versions prior to commit ce72b35a7ad0dded03051d3aa0ef75321c3bd035. An attacker who convinces a local user to open a crafted animation file can corrupt stack memory, leading to application crashes or potential code execution within the rendering process.

Critical Impact

Local exploitation through a crafted Lottie animation file can overflow a stack buffer, crashing the host application and potentially altering its execution flow. User interaction is required to trigger the vulnerable parsing path.

Affected Products

• Samsung rlottie library versions prior to commit ce72b35a7ad0dded03051d3aa0ef75321c3bd035
• Applications that embed vulnerable rlottie builds for Lottie animation rendering
• Downstream projects bundling unpatched rlottie source

Discovery Timeline

• 2026-06-04 - CVE-2026-47318 published to NVD
• 2026-06-04 - Last updated in NVD database

Technical Details for CVE-2026-47318

Vulnerability Analysis

The rlottie library parses JSON-based Lottie animation descriptors and converts them into in-memory vector representations for rendering. The vulnerable code path writes attacker-controlled data into a fixed-size stack buffer without enforcing bounds checks. When the input exceeds the buffer's capacity, adjacent stack memory, including saved return addresses and frame pointers, is overwritten.

Exploitation requires the victim to load a crafted animation file in an application linked against a vulnerable rlottie build. The attack vector is local, and the impact is concentrated on availability, with limited integrity impact and no confidentiality exposure.

The upstream fix is delivered through the GitHub Pull Request #582, merged as commit ce72b35a7ad0dded03051d3aa0ef75321c3bd035. Embedding applications must rebuild against the patched source.

Root Cause

The defect is a classic stack-based buffer overflow [CWE-121]. The parser copies variable-length values from a Lottie JSON input into a fixed-size automatic buffer without validating the input length against the destination size. Malformed or oversized fields trigger the overflow.

Attack Vector

An attacker crafts a malicious Lottie JSON file containing oversized field values that target the vulnerable parsing routine. The file is delivered through email, messaging, downloads, or any channel that culminates in a local user opening the animation in a vulnerable application. No authentication is required, but user interaction is mandatory.

No verified public proof-of-concept code is available. Refer to the upstream patch for the precise code locations modified to add bounds enforcement.

Detection Methods for CVE-2026-47318

Indicators of Compromise

• Unexpected crashes or stack corruption signatures in processes that load rlottie (librlottie.so, rlottie.dll)
• Anomalous Lottie JSON files containing unusually long string or numeric fields supplied through user-facing channels
• Core dumps showing corrupted return addresses inside rlottie parsing frames

Detection Strategies

• Inventory binaries that statically or dynamically link rlottie and verify the embedded commit hash matches the patched revision
• Inspect Lottie animation files at email and web gateways for malformed JSON structures and oversized field lengths
• Enable AddressSanitizer or stack canary diagnostics in development and QA builds to surface overflow attempts

Monitoring Recommendations

• Forward application crash telemetry and Windows Error Reporting or Linux core_pattern artifacts to a centralized analysis pipeline
• Alert on repeated abnormal terminations of processes that consume Lottie content
• Track software bill of materials (SBOM) entries for rlottie to detect unpatched components across the fleet

How to Mitigate CVE-2026-47318

Immediate Actions Required

• Rebuild and redeploy any application that bundles rlottie using source at or after commit ce72b35a7ad0dded03051d3aa0ef75321c3bd035
• Block untrusted Lottie animation files at email, messaging, and web ingress points until patched binaries are deployed
• Audit third-party dependencies and SDKs that may statically link an older rlottie revision

Patch Information

The fix is contained in commit ce72b35a7ad0dded03051d3aa0ef75321c3bd035 of the Samsung rlottie repository, merged through Pull Request #582. Upgrade by pulling the patched source from the main branch and rebuilding all dependent applications. Downstream package maintainers should publish updated binaries that reference the patched commit.

Workarounds

• Restrict the loading of Lottie animation files to trusted sources until the patched library is deployed
• Disable Lottie rendering features in applications where the functionality is non-essential
• Run consumer applications under reduced privileges to limit the impact of a successful overflow

# Configuration example: rebuild rlottie from the patched commit
git clone https://github.com/Samsung/rlottie.git
cd rlottie
git checkout ce72b35a7ad0dded03051d3aa0ef75321c3bd035
mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
cmake --build . --parallel
sudo cmake --install .