CVE-2026-47319: Samsung rlottie Buffer Overflow Vulnerability

CVE-2026-47319 Overview

CVE-2026-47319 is a memory allocation vulnerability in Samsung Open Source rlottie, an animation library used to render Lottie/JSON-based vector animations. The flaw allows excessive memory allocation when the library processes attacker-controlled size values, leading to resource exhaustion on the local system. The issue is categorized under [CWE-789] (Memory Allocation with Excessive Size Value) and affects all rlottie revisions before commit 0b4e308fa88c72cbb60cc8a2c1d2c2ad89b101dd. Exploitation requires user interaction to load a malicious animation file, and the impact is limited to local availability degradation with minor integrity loss.

Critical Impact

A crafted Lottie animation file can force rlottie to allocate excessive memory, exhausting host resources and causing the consuming application to crash or become unresponsive.

Affected Products

• Samsung Open Source rlottie library, all commits before 0b4e308fa88c72cbb60cc8a2c1d2c2ad89b101dd
• Applications and platforms that embed vulnerable rlottie builds for animation rendering
• Downstream projects bundling rlottie as a third-party dependency

Discovery Timeline

• 2026-06-04 - CVE-2026-47319 published to NVD
• 2026-06-04 - Last updated in NVD database

Technical Details for CVE-2026-47319

Vulnerability Analysis

The vulnerability resides in rlottie, a C++ library that parses and renders Lottie animations defined in JSON. During parsing, the library reads size or count fields from the input and uses those values to size internal buffers. Without an upper bound check, a maliciously crafted animation can specify extreme sizes that trigger an excessive allocation request. The host process attempts to satisfy the allocation, exhausting available memory and terminating or hanging the application that embeds the library. Because rendering libraries are commonly used in messaging clients, UI frameworks, and mobile applications, a single malformed file delivered to a user can trigger the condition.

Root Cause

The root cause is missing validation of size values consumed from untrusted input, classified as [CWE-789]. The library trusts numeric fields in the animation file and forwards them to allocation routines without enforcing a sane maximum. The upstream fix in commit 0b4e308fa88c72cbb60cc8a2c1d2c2ad89b101dd introduces bounds checking on the offending size values before allocation. The patch is tracked in the GitHub Pull Request for rlottie.

Attack Vector

The attack vector is local and requires user interaction. An attacker delivers a crafted Lottie/JSON animation file to a victim through email, messaging, a website, or a sideloaded asset. When the victim opens the file in an application that uses a vulnerable rlottie build, the parser issues an excessive allocation request. The result is a denial-of-service condition against the consuming process. No privileges are required on the target, and confidentiality is not impacted.

No public proof-of-concept exploit code is currently published. Technical details are available in the upstream pull request.

Detection Methods for CVE-2026-47319

Indicators of Compromise

• Sudden process termination or out-of-memory kills in applications that render Lottie animations
• Spikes in resident memory usage immediately after loading a .json or .lottie asset
• Crash logs referencing rlottie parsing functions or std::bad_alloc exceptions

Detection Strategies

• Inventory software builds to identify components that statically or dynamically link rlottie prior to commit 0b4e308fa88c72cbb60cc8a2c1d2c2ad89b101dd
• Inspect Lottie JSON assets for abnormally large numeric fields in size, count, or repeat parameters before rendering
• Correlate application crash telemetry with recently opened animation files or URLs that delivered them

Monitoring Recommendations

• Monitor process memory growth rates and OOM killer events on endpoints and mobile platforms that render user-supplied animations
• Alert on repeated crashes of the same renderer process across multiple hosts, which can indicate a malicious asset in circulation
• Track file delivery channels for Lottie content sourced from untrusted origins

How to Mitigate CVE-2026-47319

Immediate Actions Required

• Update rlottie to a build that includes commit 0b4e308fa88c72cbb60cc8a2c1d2c2ad89b101dd or later
• Rebuild and redistribute any internal applications that statically link the vulnerable library
• Restrict ingestion of Lottie animation files to trusted sources until patched builds are deployed

Patch Information

The fix is merged upstream in the Samsung rlottie repository at commit 0b4e308fa88c72cbb60cc8a2c1d2c2ad89b101dd. Downstream consumers should pull this revision or any subsequent release. Review the GitHub Pull Request for rlottie for the exact code changes and test coverage.

Workarounds

• Pre-validate animation files by rejecting JSON inputs that declare oversized array lengths or repeat counts
• Sandbox the rendering process and apply per-process memory limits using cgroups, ulimit, or platform equivalents
• Disable rendering of Lottie content from untrusted users in chat, email, and web applications until patches are applied

# Configuration example: cap memory for any process invoking the rlottie renderer
ulimit -v 524288  # 512 MB virtual memory ceiling
./your_app_using_rlottie animation.json