Quick answers
- Is CVE-2026-21126 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-21126 being exploited in the wild.
- How severe is CVE-2026-21126?
- Informational severity, published 12 October 2026.
- Which products and versions are affected?
- Samsung Mobile Firmware prior to SMR Oct-2026 Release 1.
- Is there a fix for CVE-2026-21126?
- Yes: fixed in SMR Oct-2026 Release 1 and later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-21126 attacked?
- It is attacked with local access, in device firmware.
- Am I affected by CVE-2026-21126?
- Check whether you run Samsung Mobile Firmware at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: SMR Oct-2026 Release 1 and later
Technical details
Improper input validation in libsimba.heifdec.media.samsung.so permits out-of-bounds memory writes during cover image extraction. The vulnerability is local in nature, requiring attacker presence on the device or ability to provide a malicious HEIF file. A successful exploit could result in code execution or memory corruption with local privilege context.
Affected products
- Samsung Mobile Firmware prior to SMR Oct-2026 Release 1
Timeline
- 2026-10-12: disclosed