CVE-2026-19517: Samsung rlottie DoS Vulnerability

CVE-2026-19517 Overview

CVE-2026-19517 is a resource allocation vulnerability in Samsung Open Source rlottie, an animation library that renders Lottie/Bodymovin JSON files. The library fails to validate quantity fields in input files and allocates resources without limits or throttling [CWE-770]. An attacker who delivers a crafted animation file can trigger excessive memory allocation, leading to a denial-of-service condition in applications embedding rlottie. Exploitation requires the victim to open or render the malicious file. The issue affects availability only; confidentiality and integrity are not impacted.

Critical Impact
A crafted Lottie animation file can exhaust host memory and crash any application that renders untrusted rlottie input, disrupting service availability.

Affected Products

Samsung Open Source rlottie animation rendering library
Applications and platforms embedding rlottie for Lottie/Bodymovin playback
Downstream integrators shipping vulnerable rlottie builds

Discovery Timeline

2026-08-11 - CVE-2026-19517 published to the National Vulnerability Database
2026-08-11 - Last updated in NVD database

Technical Details for CVE-2026-19517

Vulnerability Analysis

The flaw is categorized as Improper Validation of Specified Quantity in Input combined with Allocation of Resources Without Limits or Throttling. rlottie parses JSON-based animation descriptions that specify counts, sizes, and other numeric quantities used to size internal buffers and object arrays. Because the parser trusts these quantities without bounds checks, an attacker-controlled value drives allocation directly.

When the library processes a crafted file, it attempts to allocate memory proportional to the attacker-specified quantity. The resulting allocation can exhaust available memory, terminate the process, or destabilize the hosting application. The vulnerability affects availability of any process that loads untrusted Lottie content.

The fix landed in the upstream project through pull request 596. Refer to the Samsung rlottie Pull Request 596 for the corrective changes.

Root Cause

The root cause is missing input validation on quantity fields within Lottie JSON payloads. The parser converts attacker-supplied integers into allocation sizes without enforcing upper bounds or resource caps. There is no throttling mechanism to reject unreasonably large object counts before memory is committed.

Attack Vector

Exploitation occurs over the network path but requires user interaction. An attacker hosts or sends a malicious Lottie file that a victim opens in an application built on rlottie. Common delivery channels include web pages, chat clients, and mobile apps that render remote animation assets. Successful exploitation crashes the rendering process or the host application.

No public exploit code or proof-of-concept has been catalogued for this CVE. See the upstream patch discussion for technical context on the fix.

Detection Methods for CVE-2026-19517

Indicators of Compromise

Application crashes or out-of-memory terminations in processes that render Lottie or Bodymovin JSON files
Repeated abnormal termination of rlottie-linked binaries after opening remote animation content
Sudden memory spikes correlated with loading .json or .lottie assets from untrusted sources

Detection Strategies

Inventory applications and mobile builds that statically or dynamically link rlottie and compare against patched versions
Inspect Lottie JSON assets for unusually large numeric fields in layers, shapes, or repeater counts before they reach the parser
Correlate application crash telemetry with recent loading of externally sourced animation files

Monitoring Recommendations

Enable process crash and out-of-memory logging on endpoints that render user-supplied animations
Monitor egress fetches of Lottie assets from untrusted domains through web proxies
Track resource consumption metrics on services that convert or preview Lottie files server-side

How to Mitigate CVE-2026-19517

Immediate Actions Required

Update rlottie to a build that includes the changes from pull request 596 and rebuild dependent applications
Restrict rendering of Lottie files sourced from untrusted origins until patches are deployed
Apply resource limits to processes that parse animation content to contain memory exhaustion

Patch Information

The upstream fix is available through the Samsung rlottie repository via pull request 596. Downstream vendors and application maintainers must integrate the patched source and redistribute updated binaries. Consult the Samsung rlottie Pull Request 596 for commit details and integration guidance.

Workarounds

Pre-validate Lottie JSON files and reject payloads containing unreasonable object counts or nesting depths
Sandbox the animation renderer in a separate process with strict memory cgroups or job object limits
Disable rendering of remotely sourced animations in high-value applications until patched builds ship

bash

# Example: constrain a Linux renderer process with a memory cgroup
sudo mkdir /sys/fs/cgroup/rlottie
echo 268435456 | sudo tee /sys/fs/cgroup/rlottie/memory.max
echo $$ | sudo tee /sys/fs/cgroup/rlottie/cgroup.procs
./your_rlottie_app