CVE-2026-47320: rlottie Memory Safety Vulnerability – Uninitialized Pointer & Recursion Flaw

Technical summary

The vulnerability stems from unsafe pointer handling and missing recursion depth limits in rlottie's serialization and parsing logic. CWE-824 (access of uninitialized pointer) occurs when the library dereferences memory that was never properly initialized, potentially leaking or corrupting heap state. CWE-674 (uncontrolled recursion) allows deeply nested animation structures to exhaust the call stack. Attackers exploit this by embedding pointer references to uninitialized memory regions or creating recursive animation hierarchies within .lottie files. The issue affects rlottie versions prior to commit eae37633fda13ac05b25c6c95aacea4bc33c80a3. No CVSS vector component reflects direct code execution, but integrity (I:L) and availability (A:H) impact scores acknowledge data corruption and denial-of-service outcomes.

Business impact

Organizations integrating rlottie—commonly used in Android applications, embedded systems, and web animation rendering—face service disruptions when processing untrusted animation files. Marketing applications, design tools, and any UI-heavy mobile or web app using this library are at risk. Crashes caused by uninitialized pointer dereference may expose brief memory contents, potentially leaking sensitive data from adjacent heap allocations. The primary business impact is availability loss; secondary risk is confidentiality erosion through memory leaks. Organizations dependent on animation rendering for critical user experiences should prioritize patching.

Affected systems

Samsung rlottie is an open-source animation renderer used across Android, Linux, and web platforms. Any application statically linking or dynamically loading rlottie versions before eae37633fda13ac05b25c6c95aacea4bc33c80a3 is affected. This includes Samsung devices, third-party Android apps, Flutter and React Native integrations, and web-based animation players that embed compiled rlottie binaries. Desktop applications and embedded systems running older versions also carry risk. The vendor has not disclosed a formal product version mapping; affected parties should consult the Samsung rlottie repository and their own dependency manifests.

Exploitability

Exploitation requires local file access and user interaction—an attacker must convince a user to open a malicious .lottie or .json animation file through the target application. There is no network vector and no privilege escalation path documented. The barrier to weaponization is moderate: crafting a malformed animation file is straightforward, but delivery and social engineering are necessary. The CVSS score (6.1 MEDIUM) reflects this: low attack complexity, no elevated privileges needed, but user action mandatory. Real-world exploitation is plausible in scenarios where animation files are shared via email, messaging apps, or download sites. Active exploitation in the wild has not been confirmed as of the CVE publication date.

Remediation

Remediation centers on updating rlottie to commit eae37633fda13ac05b25c6c95aacea4bc33c80a3 or later. For applications using package managers, check for the latest stable release that includes this fix. Verify against the Samsung rlottie GitHub repository to confirm the commit is present in your target version. If rlottie is statically linked, recompile with the patched source. For web applications, redeploy with updated binaries. As a short-term mitigation, disable animation file uploads or restrict file types to pre-validated, trusted sources. Validate animation file structure before passing to rlottie parsers if possible.

Patch guidance

Samsung released the fix as commit eae37633fda13ac05b25c6c95aacea4bc33c80a3 in the rlottie open-source repository. Organizations should pull the latest main branch or track releases tagged after this commit. Update procedures vary by integration method: Android developers should check their dependency version in Gradle or Maven; web developers should rebuild with the patched native libraries; desktop applications should pull the updated library source and rebuild. No formal versioned release number is provided in the vulnerability record—verify the commit hash against your local checkout. Test animations from your actual use cases after patching to ensure rendering behavior is preserved.

Detection guidance

Monitor for application crashes or hangs when processing animation files, particularly if accompanied by memory corruption warnings or undefined behavior sanitizer (UBSan) errors. Log file access patterns for .lottie and .json files from untrusted sources. Network defenders can inspect file uploads for deeply nested JSON structures or pointer references in animation payloads, though signature-based detection is fragile. Host-based detection should flag process crashes in applications linked to rlottie and correlate them with animation file ingestion. Automated fuzzing of animation parsers with malformed inputs helps identify whether patching is complete. No publicly available intrusion detection rules exist yet; consider creating custom signatures around stack exhaustion or segmentation faults in rlottie library calls.

Why prioritize this

Prioritize patching based on deployment scope: if your organization embeds rlottie in customer-facing products or processes user-uploaded animations, treat this as high priority within the MEDIUM severity band. The uninitialized pointer weakness (CWE-824) and memory leak surface combine with the availability impact to elevate risk above a typical low-severity flaw. However, the local-only attack surface and requirement for user interaction lower urgency compared to remote, unauthenticated vectors. Schedule patching within 30–60 days for production environments; faster for products where animation file uploads are a core feature. Low-exposure systems (e.g., internal tools with curated animations) can defer further.

Risk score, explained

The CVSS 3.1 score of 6.1 (MEDIUM) balances several factors: attack vector is local (AV:L), reducing exposure; attack complexity is low (AC:L), enabling easy weaponization; no privilege escalation is needed (PR:N); user interaction is required (UI:R), a significant limiting factor. Confidentiality impact is none (C:N), but integrity is low (I:L) due to pointer corruption, and availability is high (A:H) from stack exhaustion. The score appropriately reflects that this is not a critical remote-execution flaw, yet poses a meaningful risk to systems processing untrusted animation content. The MEDIUM rating does not diminish the importance of patching; it clarifies that exploitation requires effort and local presence, not widespread network propagation.

Frequently asked questions