Vulnerabilities > CVE-2017-7112 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Apple Iphone OS
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
An issue was discovered in certain Apple products. iOS before 11 is affected. tvOS before 11 is affected. watchOS before 4 is affected. The issue involves the "Wi-Fi" component. It might allow remote attackers to execute arbitrary code in a privileged context or cause a denial of service (memory corruption) via crafted Wi-Fi traffic.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Buffer Overflow via Environment Variables This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
- Overflow Buffers Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
- Client-side Injection-induced Buffer Overflow This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
- Filter Failure through Buffer Overflow In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
- MIME Conversion An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.
Nessus
| NASL family | Misc. |
| NASL id | APPLETV_11.NASL |
| description | According to its banner, the version of Apple TV on the remote device is prior to 11. It is, therefore, affected by multiple vulnerabilities as described in the HT208113 security advisory. Note that only 4th generation models are affected by these vulnerabilities. |
| last seen | 2020-06-01 |
| modified | 2020-06-02 |
| plugin id | 103419 |
| published | 2017-09-22 |
| reporter | This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof. |
| source | https://www.tenable.com/plugins/nessus/103419 |
| title | Apple TV < 11 Multiple Vulnerabilities |
| code | |
Seebug
| bulletinFamily | exploit |
| description | Broadcom produces Wi-Fi HardMAC SoCs which are used to handle the PHY and MAC layer processing. These chips are present in both mobile devices and Wi-Fi routers, and are capable of handling many Wi-Fi related events without delegating to the host OS. On iOS, the "AppleBCMWLANBusInterfacePCIe" driver is used in order to handle the PCIe interface and low-level communication protocols with the Wi-Fi SoC (also referred to as "dongle"). Similarly, the "AppleBCMWLANCore" driver handles the high-level protocols and the Wi-Fi configuration. When the dongle wishes to notify the host OS of an event, it does so by encoding a special "packet" and transmitting it to the host. These packets have an ether type of 0x886C, and do not contain actual packet data, but rather encapsulate information about events which must be handled by the driver. One of the supported event packets is the WLC_E_TRACE message, containing a trace sent from the firmware which may be logged or stored by the host. On iOS, these events are handled by the "handleTraceEvent" function in the "AppleBCMWLANCore" driver. Each packet of this type starts with the common event message header (which is 48 bytes long), followed by the message-trace header: ``` struct msgtrace_hdr { uint8 version; uint8 trace_type; uint16 len; uint32 seqnum; uint32 discarded_bytes; uint32 discarded_printf; }; Here is a snippet of "handleTraceEvent"'s high-level logic: int64_t handleTraceEvent(void* this, uint8_t* event_packet) { struct msgtrace_hdr hdr; memmove(&hdr, event_packet + 48, sizeof(struct msgtrace_header)); if (hdr.version == 1) { ... //Is this a MSGTRACE_HDR_TYPE_MSG trace? if (hdr.trace_type == 0) { event_packet[htons(hdr.len) + 64] = 0; ... } ... } } ``` As can be seen above, for messages of type 0 no attempt is made to validate the "len" field in the msgtrace header before using it as an index into the event packet. As a result, an attacker controlling the firmware can craft a WLC_E_TRACE event packet with a large msgtrace length field, causing an OOB NUL byte to be written at the attacker-controlled 16-bit offset. |
| id | SSV:96626 |
| last seen | 2017-11-19 |
| modified | 2017-10-10 |
| published | 2017-10-10 |
| reporter | Root |
| title | Apple: OOB NUL byte write when handling WLC_E_TRACE event packets(CVE-2017-7112) |
References
- http://www.securityfocus.com/bid/100927
- http://www.securityfocus.com/bid/100927
- http://www.securitytracker.com/id/1039385
- http://www.securitytracker.com/id/1039385
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1314
- https://bugs.chromium.org/p/project-zero/issues/detail?id=1314
- https://support.apple.com/HT208112
- https://support.apple.com/HT208112
- https://support.apple.com/HT208113
- https://support.apple.com/HT208113
- https://support.apple.com/HT208115
- https://support.apple.com/HT208115