Fabrice Bellard QEMU pci_dma_read/write input validation

CVSS Meta Temp Score
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CTI Interest Score
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6.7$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Fabrice Bellard QEMU. This affects an unknown function of the file pci_dma_read/write. The manipulation leads to input validation. This vulnerability is referenced as CVE-2015-8818. Remote exploitation of the attack is possible. No exploit is available. To fix this issue, it is recommended to deploy a patch.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Fabrice Bellard QEMU (Virtualization Software) (the affected version is unknown). This issue affects an unknown code of the file pci_dma_read/write. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The cpu_physical_memory_write_rom_internal function in exec.c in QEMU (aka Quick Emulator) does not properly skip MMIO regions, which allows local privileged guest users to cause a denial of service (guest crash) via unspecified vectors.

The weakness was published 03/01/2016 as Bug 1300771 as confirmed bug report (Bugzilla). It is possible to read the advisory at bugzilla.redhat.com. The identification of this vulnerability is CVE-2015-8818 since 03/01/2016. The exploitation is known to be difficult. The attack needs to be initiated within the local network. A simple authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The following code is the reason for this vulnerability: 

len = MIN(len, (addr | iotlb.addr_mask) - addr + 1);

The vulnerability scanner Nessus provides a plugin with the ID 91660 (SUSE SLED12 / SLES12 Security Update : qemu (SUSE-SU-2016:1560-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 168944 (SUSE Enterprise Linux Security update for qemu (SUSE-SU-2016:1560-1)).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.qemu.org. A possible mitigation has been published 4 months after the disclosure of the vulnerability. The vulnerability will be addressed with the following lines of code:

*plen = MIN(*plen, (addr | iotlb.addr_mask) - addr + 1);

The vulnerability is also documented in the databases at X-Force (111188), Tenable (91660) and SecurityFocus (BID 69654†). Similar entries are available at VDB-67460, VDB-75987, VDB-81088 and VDB-81154. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.7

VulDB Base Score: 9.0
VulDB Temp Score: 7.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Unproven

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 91660
Nessus Name: SUSE SLED12 / SLES12 Security Update : qemu (SUSE-SU-2016:1560-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 55710
OpenVAS Name: SuSE Update for xen SUSE-SU-2016:1318-1 (xen)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: b242e0e0e2969c044a318e56f7988bbd84de1f63

Timelineinfo

03/01/2016 🔍
03/01/2016 +0 days 🔍
03/03/2016 +2 days 🔍
06/13/2016 +101 days 🔍
06/17/2016 +4 days 🔍
12/29/2016 +195 days 🔍
07/09/2022 +2018 days 🔍

Sourcesinfo

Vendor: bellard.org

Advisory: Bug 1300771
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-8818 (🔍)
GCVE (CVE): GCVE-0-2015-8818
GCVE (VulDB): GCVE-100-81155
X-Force: 111188 - Qemu address_space_translate denial of service
SecurityFocus: 69654

See also: 🔍

Entryinfo

Created: 03/03/2016 10:53
Updated: 07/09/2022 07:01
Changes: 03/03/2016 10:53 (66), 09/21/2018 09:33 (17), 07/09/2022 07:01 (4)
Complete: 🔍
Cache ID: 216:6F9:103

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