Quick answers
- Is CVE-2025-70293 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2025-70293 being exploited in the wild.
- How severe is CVE-2025-70293?
- Critical severity, with a CVSS score of 9.8, published 26 August 2026.
- Which products and versions are affected?
- Denx U-Boot before 2026.04.
- Is there a fix for CVE-2025-70293?
- A patch was published on 2026-04: Fix available in U-Boot 2026.04 and later Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2025-70293 attacked?
- It is attacked over the network or with local access or with physical access.
- Am I affected by CVE-2025-70293?
- Check whether you run Denx U-Boot 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.
Technical details
The vulnerability is an integer overflow in the ext4fs_get_bgdtable function that miscalculates buffer size, resulting in under-allocation. When the undersized buffer is subsequently used in memcpy(), a heap buffer overflow occurs. The vulnerability is reachable via a malicious ext4 filesystem image, which an attacker could present during boot (e.g., via USB, network boot, or a compromised storage device). Successful exploitation allows arbitrary code execution in the bootloader context. Patches are available in U-Boot version 2026.04 and later.
Affected products
- Denx U-Boot before 2026.04
Timeline
- 2026-08-26: disclosed
- 2026-04: patched: Fix available in U-Boot 2026.04 and later