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CVE-2016-4020
The patch_instruction function in hw/i386/kvmvapic.c in QEMU does not initialize the imm32 variable, which allows local guest OS…
Medium6.5EPSS 0.37%
- Published
- Updated
- Reserved
- Assigned by
- redhat
Description
The patch_instruction function in hw/i386/kvmvapic.c in QEMU does not initialize the imm32 variable, which allows local guest OS administrators to obtain sensitive information from host stack memory by accessing the Task Priority Register (TPR).
Timeline
ID reserved
By redhat
- 41 days later
· 41 days later
Published
- 8 years later
· 8 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium6.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.37% · top 69% of all CVEs (8 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Weakness
- n/a
Affected products
n/a
- affected n/a
References (11)
- http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=691a02e2ce0c413236a78dee6f2651c937b09fb0 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://bugzilla.redhat.com/show_bug.cgi?id=1313686 (opens in a new tab)x_refsource_CONFIRMx_transferred
- [qemu-devel] 20160407 [Qemu-devel] [PATCH] i386: kvmvapic: initialise imm32 variable (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- 86067 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- [qemu-devel] 20160407 Re: [Qemu-devel] [PATCH] i386: kvmvapic: initialise imm32 variable (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- RHSA-2017:2392 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
- GLSA-201609-01 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- USN-2974-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- [debian-lts-announce] 20181130 [SECURITY] [DLA 1599-1] qemu security update (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- RHSA-2017:2408 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
- RHSA-2017:1856 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2016-4020)Record last updated .