QEMU pvrdma_main.c uar_read/uar_write null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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6.4$0-$5k0.00

Summaryinfo

A vulnerability was found in QEMU. It has been classified as problematic. Affected is the function uar_read/uar_write of the file hw/rdma/vmw/pvrdma_main.c. Performing a manipulation results in null pointer dereference. This vulnerability is cataloged as CVE-2018-20191. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in QEMU (Virtualization Software) (unknown version). This affects the function uar_read/uar_write of the file hw/rdma/vmw/pvrdma_main.c. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

hw/rdma/vmw/pvrdma_main.c in QEMU does not implement a read operation (such as uar_read by analogy to uar_write), which allows attackers to cause a denial of service (NULL pointer dereference).

The bug was discovered 12/18/2018. The weakness was shared 12/20/2018 by Li Qiang (oss-sec). It is possible to read the advisory at openwall.com. This vulnerability is uniquely identified as CVE-2018-20191 since 12/17/2018. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/26/2024).

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 $5k-$25k. 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 106276†). The entries VDB-127948, VDB-128256, VDB-128257 and VDB-128258 are related to this item. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.4

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

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

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

12/13/2018 🔍
12/17/2018 +4 days 🔍
12/18/2018 +1 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
Researcher: Li Qiang
Status: Confirmed

CVE: CVE-2018-20191 (🔍)
GCVE (CVE): GCVE-0-2018-20191
GCVE (VulDB): GCVE-100-128259
SecurityFocus: 106276 - QEMU CVE-2018-20191 Local Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 12/21/2018 13:05
Updated: 10/26/2024 21:14
Changes: 12/21/2018 13:05 (61), 04/23/2020 09:22 (4), 06/20/2023 14:16 (3), 10/26/2024 21:14 (16)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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