CVE Details

Release Date:2018-07-30


The Linux kernel version 3.3-rc1 and later is affected by avulnerability lies in the processing of incoming L2CAP commands - ConfigRequest, and ConfigResponse messages. This info leak is a result of uninitialized stack variables that may be returned to an attacker in their uninitialized state. By manipulating the code flows that precede the handling of these configuration messages, an attacker can also gain some control over which data will be held in the uninitialized stack variables. This can allow him to bypass KASLR, and stack canaries protection - as both pointers and stack canaries may be leaked in this manner. Combining this vulnerability (for example) with the previously disclosed RCE vulnerability in L2CAP configuration parsing (CVE-2017-1000251) may allow an attacker to exploit the RCE against kernels which were built with the above mitigations. These are the specifics of this vulnerability: In the function l2cap_parse_conf_rsp and in the function l2cap_parse_conf_req the following variable is declared without initialization: struct l2cap_conf_efs efs; In addition, when parsing input configuration parameters in both of these functions, the switch case for handling EFS elements may skip the memcpy call that will write to the efs variable: ... case L2CAP_CONF_EFS: if (olen == sizeof(efs)) memcpy(&efs, (void *)val, olen); ... The olen in the above if is attacker controlled, and regardless of that if, in both of these functions the efs variable would eventually be added to the outgoing configuration request that is being built: l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs), (unsigned long) &efs); So by sending a configuration request, or response, that contains an L2CAP_CONF_EFS element, but with an element length that is not sizeof(efs) - the memcpy to the uninitialized efs variable can be avoided, and the uninitialized variable would be returned to the attacker (16 bytes).

See more information about CVE-2017-1000410 from MITRE CVE dictionary and NIST NVD

CVSS v2 metrics

NOTE: The following CVSS v2 metrics and score provided are preliminary and subject to review.

Base Score:5 Base Metrics:AV:N/AC:L/Au:N/C:P/I:N/A:N
Access Vector: Network Confidentiality Impact: Partial
Access Impact: Low Integrity Impact: None
Authentication: None required Availability Impact: None

Errata information

PlatformErrataRelease Date
Oracle Linux version 6 (dtrace-modules-3.8.13-118.21.4.el6uek)ELSA-2018-41342018-06-15
Oracle Linux version 6 (kernel)ELSA-2018-13192018-05-08
Oracle Linux version 6 (kernel-uek)ELSA-2018-41142018-05-22
Oracle Linux version 6 (kernel-uek)ELSA-2018-41342018-06-15
Oracle Linux version 7 (dtrace-modules-3.8.13-118.21.4.el7uek)ELSA-2018-41342018-06-15
Oracle Linux version 7 (kernel)ELSA-2018-10622018-04-16
Oracle Linux version 7 (kernel-uek)ELSA-2018-41142018-05-22
Oracle Linux version 7 (kernel-uek)ELSA-2018-41342018-06-15
Oracle VM version 3.3 (kernel-uek)OVMSA-2018-02312018-06-15
Oracle VM version 3.4 (kernel-uek)OVMSA-2018-02232018-05-23

This page is generated automatically and has not been checked for errors or omissions. For clarification or corrections please contact the Oracle Linux ULN team