CVE-2016-20039
Buffer overflow in MESS gamma handling enables local code execution.
Is CVE-2016-20039 being exploited?
Not confirmed. CVE-2016-20039 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.15% probability of exploitation in the next 30 days.
How severe is CVE-2016-20039?
CVE-2016-20039 is rated High with a CVSS score of 8.6. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2016-20039?
Not known from our data. No patch reference has been recorded for CVE-2016-20039, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2016-20039 affect?
CVE-2016-20039 affects Multi Emulator Super System (MESS), MESS 0.154-3.1. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2016-20039?
Upgrade to fixed version when released; otherwise validate/limit gamma input.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Local attacker can overflow a stack buffer via oversized gamma parameter to crash or gain code execution.
Patch when possible
- affected0.154-3.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.