ZeroHour

CVE-2026-76640

niche1

Unauthenticated Root RCE via BLE in Unitree G1 EDU Firmware ≤ 1.5.2

CVSS 4.0
7.7 high
EPSS
<1%p28
Published
()
Modified
AI analysis

Unitree G1 EDU firmware through version 1.5.2 chains two flaws—an unquoted heredoc variable in the WiFi provisioning script and an out-of-bounds write in the SSID chunk accumulator of the BLE GATT/WiFi provisioning stack—that require no pairing, credentials, or user interaction. An unauthenticated attacker within BLE range sends crafted BLE GATT writes that overflow a fixed BSS buffer across BLE connections, corrupting an adjacent mainloop function-pointer dispatch entry. When the cleanup path later invokes the corrupted entry, attacker-controlled data is passed to system() as uid 0, giving the attacker root code execution on the robot (CVSS 4.0: 7.7 High, adjacent attack vector). Only operators of Unitree G1 EDU humanoid robots running firmware 1.5.2 or earlier are affected. No public proof-of-concept is known, the issue is not in CISA KEV, and EPSS estimates only a 0.3% chance of exploitation in the next 30 days, so exploitation status is currently none known.

What to do: Check the firmware version on G1 EDU units and upgrade to the first firmware release after 1.5.2 once Unitree publishes a fix. Until then, reduce BLE exposure by keeping untrusted people and devices out of Bluetooth range of the robots and disabling or supervising BLE-based WiFi provisioning. Monitor Unitree advisories, since no public PoC or known exploitation exists today.

Affected
Unitree G1 EDU firmwareall versions through and including 1.5.2
Estimated exposure
nicheunknown, but plausibly on the order of thousands to low tens of thousands of G1 EDU robots deployed worldwide — The G1 EDU is Unitree's developer/education humanoid with a limited installed base and no internet-exposed footprint, and the attack requires proximate BLE access, so exposure is bounded by Unitree's humanoid unit sales rather than public…

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

Unitree G1 EDU firmware through 1.5.2 contains multiple chained vulnerabilities in the BLE GATT server and WiFi provisioning stack that allow unauthenticated proximate attackers to achieve root code execution without pairing or credentials by exploiting an unquoted heredoc variable in the WiFi provisioning script and a buffer overflow in the SSID chunk accumulator. Attackers can send crafted BLE writes to overflow a fixed BSS buffer across BLE connections, corrupting an adjacent mainloop function pointer dispatch entry that is subsequently invoked by the cleanup path passing attacker-controlled data to system() as uid 0.

Weakness
CWE-306, CWE-787
Vector
CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

In the news

Hack One Robot, Reach the Next: Unitree G1 Security Flaws

Researcher chained two Unitree G1 flaws (CVE-2026-76639, CVE-2026-76640) to gain unauthenticated root access, with compromised robots able to infect others via Bluetooth.

Security researcher Olivier Laflamme chained a path-traversal file-write flaw (CVE-2026-76639) in the G1 chatbot service and a Bluetooth server buffer overflow (CVE-2026-76640) to achieve unauthenticated root access remotely. The chain abuses Unitree's cloud API as a decryption oracle for the AES-128 key that unlocks BLE and WebRTC channels, and a compromised robot can propagate the attack to nearby G1 units. Unitree patched the cloud ownership-check flaw, paid a $5,000 bounty, and firmware fixes for BLE pairing and the buffer overflow remain harder to deliver.

Two Unitree G1 EDU Humanoid Robot Flaws Enable Root RCE, One Starts Over Bluetooth

Researcher disclosed two root RCE chains in Unitree G1 EDU robots (CVE-2026-76639, CVE-2026-76640), one reachable via unpaired Bluetooth, with no confirmed fixed firmware.

Security researcher Olivier Laflamme disclosed two independent root remote code execution chains in the Unitree G1 EDU robot: CVE-2026-76639, a network-adjacent path through chat_go and bashrunner, and CVE-2026-76640, a Bluetooth Low Energy path that ends with a 1,050-byte buffer overflow in btgatt-server giving root on the Locomotion PC. The BLE chain also exploits a cloud authorization gap that let any valid Unitree account recover another robot's AES key, then forces the robot onto an attacker hotspot via wpa_connect.sh heredoc injection. Unitree patched the cloud ownership check in July 2026, but no confirmed fixed firmware release addresses the BLE issues; the PoC was limited to two robots in one room and no in-the-wild exploitation is reported.