Strix
26.1K

CVE-2019-18614

HIGHCVSS 7.8/10EPSS 0.34%

Last modified

CVE-2019-18614 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. On the Cypress CYW20735 evaluation board, any data that exceeds 384 bytes is copied and causes an overflow. This is because the maximum BLOC buffer size for sending and receiving data is set to 384 bytes, but everything else is still configured to the usual size of 1092 (which was used for everything in the previous CYW20719 and later CYW20819 evaluation board). EPSS estimates a 0.34% chance of exploitation in the next 30 days.

Description

On the Cypress CYW20735 evaluation board, any data that exceeds 384 bytes is copied and causes an overflow. This is because the maximum BLOC buffer size for sending and receiving data is set to 384 bytes, but everything else is still configured to the usual size of 1092 (which was used for everything in the previous CYW20719 and later CYW20819 evaluation board). To trigger the overflow, an attacker can either send packets over the air or as unprivileged local user. Over the air, the minimal PoC is sending "l2ping -s 600" to the target address prior to any pairing. Locally, the buffer overflow is immediately triggered by opening an ACL or SCO connection to a headset. This occurs because, in WICED Studio 6.2 and 6.4, BT_ACL_HOST_TO_DEVICE_DEFAULT_SIZE and BT_ACL_DEVICE_TO_HOST_DEFAULT_SIZE are set to 384.

Metrics

CVSS 3.1
7.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability
0.34%

25.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
CypressCyw20735 FirmwareAll versions

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2019-18614?
On the Cypress CYW20735 evaluation board, any data that exceeds 384 bytes is copied and causes an overflow. This is because the maximum BLOC buffer size for sending and receiving data is set to 384 bytes, but everything else is still configured to the usual size of 1092 (which was used for everything in the previous CYW20719 and later CYW20819 evaluation board). To trigger the overflow, an attacker can either send packets over the air or as unprivileged local user. Over the air, the minimal PoC is sending "l2ping -s 600" to the target address prior to any pairing. Locally, the buffer overflow is immediately triggered by opening an ACL or SCO connection to a headset. This occurs because, in WICED Studio 6.2 and 6.4, BT_ACL_HOST_TO_DEVICE_DEFAULT_SIZE and BT_ACL_DEVICE_TO_HOST_DEFAULT_SIZE are set to 384.
How severe is CVE-2019-18614?
CVE-2019-18614 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.
How do I fix CVE-2019-18614?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-18614?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST