VDB-81711 · CVE-2016-2858 · BID 84134

QEMU PRNG Backend Support Entropy Request memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability classified as problematic has been found in QEMU (Virtualization Software) (version unknown). This affects an unknown function of the component PRNG Backend Support. The manipulation as part of a Entropy Request leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

QEMU, when built with the Pseudo Random Number Generator (PRNG) back-end support, allows guest OS users to cause a denial of service (process crash) via an entropy request, which triggers arbitrary stack based allocation and memory corruption.

The weakness was released 04/07/2016 by Prasad J Pandit with Red Hat (Website). It is possible to read the advisory at git.qemu.org. This vulnerability is uniquely identified as CVE-2016-2858 since 03/06/2016. Attacking locally is a requirement. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 90036 (Fedora 22 : xen-4.5.2-9.fc22 (2016-38b20aa50f)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176848 (Debian Security Update for qemu (DLA 1599-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (90036). Entries connected to this vulnerability are available at 81088, 81198, 82912 and 87559.





CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
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VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 5.9
VulDB Temp Score: 5.7
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NVD Base Score: 5.9
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Class: Memory corruption
CWE: CWE-119
ATT&CK: Unknown

Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

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Current Price Estimation: 🔍


Nessus ID: 90036
Nessus Name: Fedora 22 : xen-4.5.2-9.fc22 (2016-38b20aa50f)
Nessus File: 🔍
Nessus Risk: 🔍
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OpenVAS ID: 867773
OpenVAS Name: Fedora Update for qemu FEDORA-2016-f2b1f07256
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
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Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Patch: 60253ed1e6ec6d8e5ef2efe7bf755f475dce9956


03/04/2016 🔍
03/06/2016 +2 days 🔍
03/19/2016 +13 days 🔍
03/21/2016 +2 days 🔍
03/21/2016 +0 days 🔍
04/07/2016 +16 days 🔍
04/07/2016 +0 days 🔍
04/08/2016 +1 days 🔍
04/12/2016 +4 days 🔍
07/12/2022 +2282 days 🔍


Product: qemu.org

Advisory: FEDORA-2016-38b20aa50f
Researcher: Prasad J Pandit
Organization: Red Hat
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2016-2858 (🔍)
Vulnerability Center: 58066 - QEMU built with Pseudo Random Number Generator Back-End Support Local DoS Vulnerability, Low
SecurityFocus: 84134 - Qemu 'rng-random.c' Denial of Service Vulnerability

See also: 🔍


Created: 04/08/2016 10:44 AM
Updated: 07/12/2022 01:37 PM
Changes: 04/08/2016 10:44 AM (68), 02/04/2019 11:40 AM (16), 07/12/2022 01:31 PM (5), 07/12/2022 01:37 PM (1)
Complete: 🔍


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