CVE-2020-15802
published 2020-09-11CVE-2020-15802: Devices supporting Bluetooth before 5.1 may allow man-in-the-middle attacks, aka BLURtooth. Cross Transport Key Derivation in Bluetooth Core Specification v4.2…
PriorityP337medium5.9CVSS 3.1
AVNACHPRNUINSUCNIHAN
EPSS
7.14%
93.6th percentile
Devices supporting Bluetooth before 5.1 may allow man-in-the-middle attacks, aka BLURtooth. Cross Transport Key Derivation in Bluetooth Core Specification v4.2 and v5.0 may permit an unauthenticated user to establish a bonding with one transport, either LE or BR/EDR, and replace a bonding already established on the opposing transport, BR/EDR or LE, potentially overwriting an authenticated key with an unauthenticated key, or a key with greater entropy with one with less.
Affected
7 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| bluetooth | bluetooth_core_specification | < 5.1 | 5.1 |
| android | — | — | |
| platform | system_bt | >= 10:0 < 10:2020-12-01 | 10:2020-12-01 |
| platform | system_bt | >= 11:0 < 11:2020-12-01 | 11:2020-12-01 |
| platform | system_bt | >= 8.0:0 < 8.0:2020-12-01 | 8.0:2020-12-01 |
| platform | system_bt | >= 8.1:0 < 8.1:2020-12-01 | 8.1:2020-12-01 |
| platform | system_bt | >= 9:0 < 9:2020-12-01 | 9:2020-12-01 |
Detection & IOCsextracted from sources · hover to see the quote
- →Monitor for unauthenticated Bluetooth pairing attempts (e.g., Just Works association) on one transport (LE or BR/EDR) that result in key derivation or key overwrite on the opposing transport via CTKD ↗
- →Alert on Bluetooth pairing events where an existing authenticated or higher-entropy key is replaced by an unauthenticated or lower-entropy key across transports (BR/EDR ↔ LE) ↗
- →Audit Android devices running AOSP 8.0, 8.1, 9, 10, or 11 for the BLURtooth/CTKD vulnerability (Android bug reference A-158854097) ↗
- →Detect Bluetooth chips from Broadcom, CSR, Cypress, Intel, and Qualcomm supporting Bluetooth 4.2, 5.0, 5.1, or 5.2 (all CTKD-capable versions) as potentially vulnerable targets ↗
- ·The /etc/bluetooth/main.conf ControllerMode setting can restrict the Bluetooth controller to a single transport (bredr or le), eliminating the dual-mode attack surface; default is 'dual' ↗
- ·The Bluetooth SIG claimed Bluetooth 5.1 and later are not vulnerable, but the researchers found 5.1 and 5.2 devices to still be susceptible in practice ↗
- ·The attack does not require the attacker to be present during the original pairing event, unlike prior Bluetooth attacks, making passive detection of the initial pairing insufficient ↗
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:P/A:N
osv5.9MEDIUM
vendor_redhat5.9MEDIUM
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GHSA
GHSA-2ffq-f4m4-q248: Devices supporting Bluetooth before 5
ghsa_unreviewed·2022-05-24
CVE-2020-15802 [MEDIUM] CWE-287 GHSA-2ffq-f4m4-q248: Devices supporting Bluetooth before 5
Devices supporting Bluetooth before 5.1 may allow man-in-the-middle attacks. Cross Transport Key Derivation in Bluetooth Core Specification v4.2 and v5.0 may permit an unauthenticated user to establish a bonding with one transport, either LE or BR/EDR, and replace a bonding already established on the opposing transport, BR/EDR or LE, potentially overwriting an authenticated key with an unauthenticated key, or a key with greater entropy with one with less.
OSV
CVE-2020-15802: In smp_key_distribution of smp_act
osv·2020-12-01
CVE-2020-15802 CVE-2020-15802: In smp_key_distribution of smp_act
In smp_key_distribution of smp_act.cc, there are possible vulnerabilities in Cross-Transport Key Derivation due to weaknesses in the Bluetooth standard. This could lead to remote information disclosure with no additional execution privileges needed. User interaction is not needed for exploitation.
OSV
CVE-2020-15802: Devices supporting Bluetooth before 5
osv·2020-09-11·CVSS 5.9
CVE-2020-15802 [MEDIUM] CVE-2020-15802: Devices supporting Bluetooth before 5
Devices supporting Bluetooth before 5.1 may allow man-in-the-middle attacks, aka BLURtooth. Cross Transport Key Derivation in Bluetooth Core Specification v4.2 and v5.0 may permit an unauthenticated user to establish a bonding with one transport, either LE or BR/EDR, and replace a bonding already established on the opposing transport, BR/EDR or LE, potentially overwriting an authenticated key with an unauthenticated key, or a key with greater entropy with one with less.
Android
CVE-2020-15802: Android Security Bulletin 2020-12-01
CVE: CVE-2020-15802
Severity: HIGH
Type: ID
Affected AOSP versions: 8
vendor_android·2020-12-01·CVSS 5.9
CVE-2020-15802 [MEDIUM] CVE-2020-15802: Android Security Bulletin 2020-12-01
CVE: CVE-2020-15802
Severity: HIGH
Type: ID
Affected AOSP versions: 8
Android Security Bulletin 2020-12-01
CVE: CVE-2020-15802
Severity: HIGH
Type: ID
Affected AOSP versions: 8.0, 8.1, 9, 10, 11
References: A-158854097
Red Hat
hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite
vendor_redhat·2020-09-10·CVSS 5.9
CVE-2020-15802 [MEDIUM] CWE-285 hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite
hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite
Devices supporting Bluetooth before 5.1 may allow man-in-the-middle attacks, aka BLURtooth. Cross Transport Key Derivation in Bluetooth Core Specification v4.2 and v5.0 may permit an unauthenticated user to establish a bonding with one transport, either LE or BR/EDR, and replace a bonding already established on the opposing transport, BR/EDR or LE, potentially overwriting an authenticated key with an unauthenticated key, or a key with greater entropy with one with less.
A flaw was found in the bluetooth specification that would allow an attacker within bluetooth radio range to abuse a protocol flaw which could allow key-overwrite in services.
Statement: Red Hat Product Security is aware of this issue. U
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2020-15802 hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite
bugzilla·2020-09-11·CVSS 5.9
CVE-2020-15802 [MEDIUM] CVE-2020-15802 hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite
CVE-2020-15802 hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite
A flaw was found in the way the Bluetooth Security Manager, as implemented in the Linux kernel, handles encryption keys propagation between BR/EDR and LE physical transports.
On systems that enabled pairing over both physical transports simultaneously (so called dual-mode systems) it is possible for an attacker to pair using the first transport with a weaker authentication method which then also resulted in encryption key update for the second transport with key derived from the first via feature called Cross-Transport Key Derivation (CKTD).
An attacker in the Bluetooth adjacent range could use this flaw to potentially access Bluetooth resources on the system that he otherwise would be un
Bugzilla
CVE-2020-15802 kernel: hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite [fedora-all]
bugzilla·2020-09-11·CVSS 5.9
CVE-2020-15802 [MEDIUM] CVE-2020-15802 kernel: hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite [fedora-all]
CVE-2020-15802 kernel: hardware: BLURtooth: "Dual mode" hardware using CTKD are vulnerable to key overwrite [fedora-all]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of fedora-all.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
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Please also mention the CVE IDs being fixed in the RPM changelog and the
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NOTE: thi
arXiv
BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy
arxiv_fulltext·2021-11-08
BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy
BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy
Daniele Antonioli
EURECOM
Nils Ole Tippenhauer
CISPA Helmholtz Center
Kasper Rasmussen
University of Oxford
Mathias Payer
EPFL
## Abstract
The Bluetooth standard specifies two transports: Bluetooth Classic (BT)
for high-throughput wireless services and Bluetooth Low Energy (BLE) for
very low-power scenarios. BT and BLE have dedicated pairing protocols and
devices have to pair over BT and BLE to use both securely. In 2014, the
Bluetooth standard (v4.2) addressed this usability issue by introducing
Cross-Transport Key Derivation (CTKD). CTKD allows establishing BT and
BLE pairing keys just by pairing over one of the two transports. While CTKD
crosses the security boundary between BT and BLE,
arXiv
BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy
arxiv_cs_cr·2021-11-08·CVSS 5.9
[MEDIUM] BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy
BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy
The Bluetooth standard specifies two transports: Bluetooth Classic (BT) for high-throughput wireless services and Bluetooth Low Energy (BLE) for very low-power scenarios. BT and BLE have dedicated pairing protocols and devices have to pair over BT and BLE to use both securely. In 2014, the Bluetooth standard (v4.2) addressed this usability issue by introducing Cross-Transport Key Derivation (CTKD). CTKD allows establishing BT and BLE pairing keys just by pairing over one of the two transports. While CTKD crosses the security boundary between BT and BLE, little is known about the internals of CTKD and its security implications.
In this work, we present the first complete description of CTKD o
Checkpoint
14th September – Threat Intelligence Bulletin
blogs_checkpoint·2020-09-14
CVE-2020-2040 14th September – Threat Intelligence Bulletin
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## 14th September – Threat Intelligence Bulletin
For the latest discoveries in cyber research for the week of 14th September 2020, please download our Threat Intelligence Bulletin .
Top Attacks and Breaches
US data center giant Equinix has been hit by the Netwalker ransomware. The threat actor demanded $4.5 million worth of bitcoin in exchange for decryption keys and to prevent release of stolen data. Also hit by Netwalker were Argentina’s immigration agency , and the largest power supplier in Pakistan, K-Electric
https://gizmodo.com/bluetooth-unveils-its-latest-security-issue-with-no-se-1845013709https://www.bluetooth.com/learn-about-bluetooth/bluetooth-technology/bluetooth-security/blurtooth/https://www.kb.cert.org/vuls/id/589825https://gizmodo.com/bluetooth-unveils-its-latest-security-issue-with-no-se-1845013709https://www.bluetooth.com/learn-about-bluetooth/bluetooth-technology/bluetooth-security/blurtooth/https://www.kb.cert.org/vuls/id/589825
2020-09-11
Published