QEMU hw/rdma/rdma_backend.c num_sge out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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5.4$0-$5k0.66

Summaryinfo

A vulnerability, which was classified as critical, was found in QEMU. The impacted element is an unknown function of the file hw/rdma/rdma_backend.c. The manipulation of the argument num_sge results in out-of-bounds. This vulnerability is identified as CVE-2018-20124. The attack is only possible with local access. There is not any exploit available.

Detailsinfo

A vulnerability was found in QEMU (Virtualization Software) (affected version not known). It has been classified as critical. Affected is some unknown functionality of the file hw/rdma/rdma_backend.c. The manipulation of the argument num_sge with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

hw/rdma/rdma_backend.c in QEMU allows guest OS users to trigger out-of-bounds access via a PvrdmaSqWqe ring element with a large num_sge value.

The bug was discovered 12/18/2018. The weakness was released 12/20/2018 (oss-sec). The advisory is shared for download at openwall.com. This vulnerability is traded as CVE-2018-20124 since 12/13/2018. The exploitability is told to be easy. The attack needs to be approached locally. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 2 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 209571 (Oracle Linux 8 : virt:kvm_utils3 (ELSA-2024-12792)), which helps to determine the existence of the flaw in a target environment. The commercial vulnerability scanner Qualys is able to test this issue with plugin 157908 (Oracle Enterprise Linux Security Update for qemu (ELSA-2019-4518)).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (209571) and SecurityFocus (BID 106290†). Entries connected to this vulnerability are available at VDB-127948, VDB-128257, VDB-128258 and VDB-128259. VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 209571
Nessus Name: Oracle Linux 8 : virt:kvm_utils3 (ELSA-2024-12792)

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/12/2018 🔍
12/13/2018 +1 days 🔍
12/18/2018 +5 days 🔍
12/20/2018 +2 days 🔍
12/20/2018 +0 days 🔍
12/21/2018 +1 days 🔍
10/26/2024 +2136 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: USN-3923-1
Status: Confirmed

CVE: CVE-2018-20124 (🔍)
GCVE (CVE): GCVE-0-2018-20124
GCVE (VulDB): GCVE-100-128256
SecurityFocus: 106290 - QEMU 'hw/rdma/rdma_backend.c' Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 12/21/2018 13:01
Updated: 10/26/2024 21:05
Changes: 12/21/2018 13:01 (61), 04/23/2020 09:10 (3), 06/20/2023 14:04 (3), 10/26/2024 21:05 (17)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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