CVE-2016-9383: citrix xenserver Improper Input Validation
Vulnerability summary
CVE-2016-9383 is a high (CVSS 8.8) Improper Input Validation vulnerability in citrix xenserver. EPSS estimates a 0.51% chance of exploitation in the next 30 days, higher than 43.1% of scored vulnerabilities.
Not severe (CVSS 8.8, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 10 · Related 7Timeline
- 23-01-2017PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
Description
Xen, when running on a 64-bit hypervisor, allows local x86 guest OS users to modify arbitrary memory and consequently obtain sensitive information, cause a denial of service (host crash), or execute arbitrary code on the host by leveraging broken emulation of bit test instructions.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated8.8HighCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated8.8HighCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS trend
Probability
0.51%
Chance of exploitation in the next 30 days
Percentile
43%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.51% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine1 product
- xen< 4.7.1-r1
Citrix1 product
- xenserver6.0.2 | 6.2.0 | 6.5 | 7.0
Debian1 product
- xen< 4.8.0-1
Ubuntu1 product
- xen< 4.4.2-0ubuntu0.14.04.9 | < 4.6.0-1ubuntu4.3
4 vendors · 4 products