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

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$0-$5k0.00

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 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 vulnerability database at SecurityFocus (BID 106290†).

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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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 🔍
06/20/2023 +1642 days 🔍

Sourcesinfo

Product: qemu.org

Advisory: USN-3923-1
Status: Confirmed

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

Entryinfo

Created: 12/21/2018 01:01 PM
Updated: 06/20/2023 02:04 PM
Changes: 12/21/2018 01:01 PM (61), 04/23/2020 09:10 AM (3), 06/20/2023 02:04 PM (3)
Complete: 🔍
Cache ID: 98:736:40

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