Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V14 - Data Protection Sensitive info in resource not removed before reuse
|
| Impact | The CVSS v4.0 score of 5.1 reflects a physical attack vector (AV:P) with low attack complexity (AC:L), no privileges required (PR:N), and high confidentiality impact (VC:H)-appropriate for a firmware disclosure issue accessible only via direct SPI interface tampering. The attack vector constraint (AV:P) significantly limits real-world exploitability compared to network-based vulnerabilities; an attacker must have hands-on physical access to the device's SPI pins or debugging interface, making opportunistic exploitation infeasible in most deployments. However, for adversaries with supply-chain access, device interdiction capabilities, or insider threats, this presents a genuine risk for extracting proprietary firmware and deriving cryptographic keys or algorithmic details. No EPSS, KEV status, or public exploit code has been reported, and the vulnerability affects only early firmware versions, suggesting remediation is already available or actively deployed. The real-world priority depends on the deployment context: consumer IoT devices in field locations represent lower risk, while critical infrastructure, military, or high-security LoRa deployments warrant urgent patching. From an SSVC perspective, exploitation is technically possible but not automatable (requires physical access), and the technical impact is limited to confidentiality (firmware disclosure), not integrity or availability of the device itself. |
| Exploit ScenarioDerived | An attacker with physical access to a deployed LoRa device (e.g., through supply-chain interception or field access) probes the SPI interface using standard debugging tools (logic analyzer, bus pirate, or custom FPGA). The attacker triggers the firmware validity check command to cause the device to decrypt firmware blocks, then immediately issues SPI read commands to extract the uncleared last decrypted block from the transceiver's memory buffer. By repeating this process across multiple validation cycles or by accessing different regions of the device's RAM, the attacker reconstructs the complete decrypted firmware, obtaining proprietary algorithms, cryptographic keys, or device identifiers. No sophisticated exploit toolkit is required-commodity hardware and standard SPI protocol knowledge suffice-but the attack requires direct physical device access, limiting its scope primarily to supply-chain threats or insider scenarios. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Apr 07, 2026
Information disclosure vulnerability in Semtech LR11xx LoRa transceivers (LR1110, LR1120, LR1121) allows attackers with physical SPI interface access to retrieve decrypted firmware contents by exploiting improper memory cleanup after firmware validation. The device fails to clear the last decrypted firmware block from memory after integrity checks complete, enabling an attacker to bypass firmware encryption protection via subsequent SPI memory read commands. This affects early firmware versions and requires direct physical access to the SPI interface.
RemediationAI
Upgrade to patched firmware versions released by Semtech. The vendor's PSA-2026-001 security bulletin (https://www.semtech.com/company/security/security-bulletins/sem-psa-2026-001) provides specific firmware version numbers and distribution guidance. The fix involves clearing (zeroizing) decrypted firmware blocks from memory immediately after validation completes, preventing residual plaintext from being accessible via subsequent SPI reads. For organizations unable to immediately upgrade, implement additional physical security controls such as epoxy coating of SPI debug pins, tamper detection mechanisms, or secure enclosures that prevent unauthorized SPI interface access. Supply-chain integrity verification and device authentication checks should be prioritized for deployments in high-security contexts.
Affected VersionsENISA
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The Semtech LR11xx series are ultra-low-power LoRa transceivers that support encrypted firmware updates via the SPI (Serial Peripheral Interface) protocol. The vulnerability exists in the firmware validation subsystem, which implements block-by-block decryption of encrypted firmware packages to verify integrity before deployment. The root cause is improper resource cleanup (CWE-226: Sensitive Information in Memory) in the validation routine-specifically, failure to zeroize cryptographic buffers after the validation operation completes. When the host issues a firmware validity check command, the device decrypts firmware blocks sequentially but leaves the final decrypted block resident in memory. Subsequent SPI read commands can access this uncleared memory region, effectively leaking decrypted firmware contents and negating the protection provided by firmware encryption. Affected products include LR1110 (all versions per CPE cpe:2.3:a:semtech:lr1110:*:*:*:*:*:*:*:*), LR1120, and LR1121 transceivers running early firmware revisions.
Know when Lr1110 gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/AU:N/R:A/V:C/RE:M
Primary rating from Vendor (SWI) · only source for this CVE.
CVSS VectorVendor: SWI
DescriptionCVE.org
The Semtech LR11xx LoRa transceivers running early versions of firmware contains an information disclosure vulnerability in its firmware validation functionality. When a host issues a firmware validity check command via the SPI interface, the device decrypts the provided encrypted firmware package block-by-block to validate its integrity. However, the last decrypted firmware block remains uncleared in memory after the validation process completes. An attacker with access to the SPI interface can subsequently issue memory read commands to retrieve the decrypted firmware contents from this residual memory, effectively bypassing the firmware encryption protection mechanism. The attack requires physical access to the device's SPI interface.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.
Cryptographic bypass in Semtech LR11xx LoRa transceiver secure boot allows physically proximate attackers to install arb
Stack memory write protection bypass in Semtech LoRa LR11xx transceiver firmware allows physical attackers with SPI inte
EUVD-2025-209284
GHSA-pq38-4mfg-vpxj
NVD
CVE.org
EPSS
Vulnrichment
Exploit-DB