Xen up to 4.13.x GNTTABOP_copy denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.4$0-$5k0.00

A vulnerability, which was classified as problematic, was found in Xen up to 4.13.x (Virtualization Software). Affected is the function GNTTABOP_copy. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. CVE summarizes:

An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of bad continuation handling in GNTTABOP_copy. Grant table operations are expected to return 0 for success, and a negative number for errors. The fix for CVE-2017-12135 introduced a path through grant copy handling where success may be returned to the caller without any action taken. In particular, the status fields of individual operations are left uninitialised, and may result in errant behaviour in the caller of GNTTABOP_copy. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to copy a grant, it hits the incorrect exit path. This returns success to the caller without doing anything, which may cause crashes or other incorrect behaviour.

The weakness was published 04/14/2020 (oss-sec). The advisory is shared for download at openwall.com. This vulnerability is traded as CVE-2020-11742 since 04/14/2020. 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 current price for an exploit might be approx. USD $0-$5k (estimation calculated on 04/15/2020).

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

Similar entries are available at 153121, 153119, 153118 and 153117.

Productinfo

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Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.4

VulDB Base Score: 3.3
VulDB Temp Score: 3.3
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: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

04/14/2020 🔍
04/14/2020 +0 days 🔍
04/15/2020 +1 days 🔍
04/15/2020 +0 days 🔍

Sourcesinfo

Advisory: openwall.com
Status: Not defined
Confirmation: 🔍

CVE: CVE-2020-11742 (🔍)
See also: 🔍

Entryinfo

Created: 04/15/2020 08:07
Updated: 04/15/2020 08:12
Changes: 04/15/2020 08:07 (38), 04/15/2020 08:12 (18)
Complete: 🔍
Cache ID: 3:BBA:103

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