CVE-2026-10305: Out-of-Bounds Read in Samsung rlottie Animation Library

Technical summary

CVE-2026-10305 is an out-of-bounds read vulnerability in rlottie, Samsung's open-source Lottie animation rendering engine. The flaw exists in buffer handling logic prior to commit 223a2a41ba4f462e4abe767bebba49a366c9b9fd. Categorized as CWE-125 (Out-of-bounds Read), the vulnerability permits reading memory beyond allocated buffer bounds during animation file parsing or rendering. The CVSS 3.1 score of 6.1 reflects local attack surface (AV:L), low complexity exploitation, no privilege requirements, user interaction dependency, and impacts to integrity and availability—but not confidentiality.

Business impact

Applications embedding rlottie to render user-supplied or untrusted Lottie animation files face integrity and stability risks. An attacker could craft a malicious .lottie or .json animation file that, when processed, causes the application to read out-of-bounds memory, leading to crashes or potential data corruption. In scenarios where rlottie is used in content-sharing platforms, mobile apps, or design tools, this could result in denial of service affecting end-user experience. The integrity impact suggests potential corruption of application state or data structures, though confidentiality leakage is not the primary concern.

Affected systems

Any deployment of rlottie prior to commit 223a2a41ba4f462e4abe767bebba49a366c9b9fd is affected. This includes direct integrations of the rlottie library in applications, as well as third-party tools and platforms that bundle or depend on vulnerable versions of rlottie. Organizations should inventory rlottie usage across web applications, mobile apps, desktop tools, and embedded systems. The vulnerability does not appear on the CISA Known Exploited Vulnerabilities catalog, suggesting current exploitation in the wild is not documented, but that status can change.

Exploitability

Exploitation requires local access and user interaction—specifically, a user must open or process a crafted animation file. The attack complexity is low, meaning a standard animation file can be weaponized without additional system-level preconditions. An attacker could distribute malicious .lottie files via email, file-sharing services, or social engineering to trigger the vulnerability. Remote exploitation is not possible; however, the low barrier to crafting a trigger file and the ease of social delivery make this a practical attack vector in real-world scenarios.

Remediation

Update rlottie to a version incorporating commit 223a2a41ba4f462e4abe767bebba49a366c9b9fd or later. Verify the exact release version with Samsung's official rlottie repository or security advisory. Organizations should perform a software bill of materials (SBOM) review to identify all direct and transitive dependencies on rlottie, then prioritize patching in order of user-facing and high-traffic applications. Until patches can be applied, implement application-level controls to validate and sanitize animation files before processing.

Patch guidance

Consult Samsung's official rlottie repository and security advisories for verified release versions containing the fix. The patch commit is 223a2a41ba4f462e4abe767bebba49a366c9b9fd; confirm your target version includes this or a later commit. For organizations using rlottie as an indirect dependency through another framework or library, check for updated releases of those upstream projects. Test patches in a staging environment with your application's animation rendering workflows before production deployment to ensure no compatibility regressions.

Detection guidance

Monitor for crashes or exceptions in application components that process animation files, particularly stack traces mentioning memory access violations in rlottie code paths. Implement runtime monitoring and fuzzing of animation file ingestion to detect out-of-bounds reads. Code review and static analysis can identify calls to rlottie functions parsing untrusted animation input. For deployed systems, enable application profiling and memory protection features (ASLR, stack canaries) to make exploitation more difficult and detect anomalies early. Log file processing events and unusual animation file characteristics.

Why prioritize this

Although CVE-2026-10305 carries a MEDIUM severity score and does not appear on active exploitation lists, it should not be deprioritized. The combination of low exploitation complexity, practical attack delivery (malicious animation files), and availability/integrity impact makes it a moderate-priority item for development and QA teams. Organizations that process user-supplied animations or expose animation rendering in public-facing features should prioritize this patch. Standard business criticality assessment (Does your app handle animations? Are they user-supplied?) should drive scheduling alongside other vulnerability remediation efforts.

Risk score, explained

The CVSS 3.1 score of 6.1 (MEDIUM) reflects the following factors: local attack vector limits remote exploitation; low attack complexity means minimal attacker sophistication; no privilege escalation required; user interaction (opening a file) is necessary; scope is unchanged; confidentiality is not impacted; integrity is partially impacted (the 'I' flag); availability is highly impacted (the 'A' flag). The integrity and availability combination elevates risk beyond a low score, justifying proactive patching despite MEDIUM classification.

Frequently asked questions