How severe is CVE-2016-0034?

CVE-2016-0034 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2016-0034?

Affected package information for CVE-2016-0034 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2016-0034?

No fixed release is recorded for CVE-2016-0034 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.

How do I detect CVE-2016-0034 in my code and dependencies?

Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).

How do I mitigate CVE-2016-0034 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2016-0034 actively exploited in the wild?

Yes. There are 2 known exploit references for CVE-2016-0034, including 2 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2016-0034?

CVE-2016-0034 has an EPSS (Exploit Prediction Scoring System) score of 69.4%, placing it in the 99th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2016-0034 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2016-0034 (Microsoft Silverlight Runtime Remote Code Execution Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-05-25. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-06-15. The required action was: The impacted products are end-of-life and should be disconnected if still in use. This CVE has been used in known ransomware campaigns. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

When was CVE-2016-0034 published, and has it been updated?

CVE-2016-0034 was published on January 13, 2016 and was last updated on August 14, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🛡️

CISA KEV · ACTIVELY EXPLOITED

HIGH severity

CVE-2016-0034 — Microsoft

HIGH

CVE-2016-0034 is a high-severity (CVSS 8.8) remote code execution vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2022-05-25) and has been used in ransomware campaigns — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.

Microsoft Silverlight 5 before 5.1.41212.0 mishandles negative offsets during decoding, which allows remote attackers to execute arbitrary code or cause a denial of service (object-header…

Published

Jan 13, 2016

Updated

Aug 14, 2026

Affected

1 product

Patched

See advisory

Exploits

2 known

Exploitation data as of Oct 24, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2022-05-25 — including use in ransomware campaigns. Federal agencies were required to remediate by 2022-06-15.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2016-0034.

EPSS Exploitation Probability

via FIRST.org ↗

69.4%probability of exploitation in next 30 days

High Risk0.00%

Lower risk than most CVEs99th percentile — riskier than 99% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2016-0034 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Counts from FIRST.org, log-scaled.

Description

Microsoft Silverlight 5 before 5.1.41212.0 mishandles negative offsets during decoding, which allows remote attackers to execute arbitrary code or cause a denial of service (object-header corruption) via a crafted web site, aka "Silverlight Runtime Remote Code Execution Vulnerability."

Affected Products

1 product · 1 configurations

Application

silverlightmicrosoft

≥ 5.0 && < 5.1.41212.0

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Microsoft Silverlight 5 before 5.1.41212.0 mishandles negative offsets d…

docs.microsoft.comGoogle-sheetNov 2015

Microsoft Silverlight 5 before 5.1.41212.0 mishandles negative offsets d…

cisa.govCISAMay 2022

Detection & mitigation playbook

Vulnerability

Detect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
No fixed release is recorded for CVE-2016-0034 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2016-0034 in your dependencies?

Find it across , including transitive dependencies.

Scan my dependencies How O3 SCA works