What is CVE-2018-4878?

CVE-2018-4878 is a high-severity vulnerability in Adobe Flash Player, classified under Use After Free. CVSS score: 7.8/10. Published 2018-02-06.

How severe is CVE-2018-4878?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2018-4878 known to be exploited?

Yes. CVE-2018-4878 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 131 public proof-of-concept repositories are indexed.

Use After Free in Adobe Flash Player

CVE-2018-4878

A use-after-free vulnerability was discovered in Adobe Flash Player before 28.0.0.161. This vulnerability occurs due to a dangling pointer in the Primetime SDK related to media player handling of listener objects. A successful attack can lead to arbitrary code execution. This was exploited in the wild in January and February 2018.

Vulnerability class: Use-After-Free

Published 2018-02-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.895 (99.8th percentile), scored 2026-10-19.

High probability of exploitation in the next 30 days — patch promptly. 100th percentile — 99.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.895 · newest: 0.895 · change: 0.000

Affected products

Adobe Flash Player
Apple macOS
Google Chrome OS
Linux Kernel
Microsoft Windows
Microsoft Windows 10
Microsoft Windows 8.1
Red Hat Enterprise Linux Desktop — versions 6.0
Red Hat Enterprise Linux Server — versions 6.0
Red Hat Enterprise Linux Workstation — versions 6.0

Weakness classification (CWE)

CWE-416 — Use After Free

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2021-11-03. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2022-05-03.

Required action: The impacted product is end-of-life and should be disconnected if still in use.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

blog.talosintelligence.com/2018/02/group-123-goes-wild.html (Technical Description, Third Party Advisory)
threatpost.com/adobe-flash-player-zero-day-spotted-in-the-wild/129742/ (Third Party Advisory)
helpx.adobe.com/security/products/flash-player/apsb18-03.html (Vendor Advisory)
access.redhat.com/errata/RHSA-2018:0285 (vendor-advisory, Third Party Advisory)
www.securitytracker.com/id/1040318 (vdb-entry, Broken Link)
www.securityfocus.com/bid/102893 (vdb-entry, Broken Link)
www.fireeye.com/blog/threat-research/2018/02/attacks-leveraging-adobe-zero-day… (Third Party Advisory)
blog.morphisec.com/flash-exploit-cve-2018-4878-spotted-in-the-wild-massive-mals… (Third Party Advisory)
www.darkreading.com/threat-intelligence/adobe-flash-vulnerability-reappears-in-… (Third Party Advisory, Press/Media Coverage)
github.com/InQuest/malware-samples/tree/master/CVE-2018-4878-Adobe-Flash-DRM-UA… (Third Party Advisory)

Frequently asked questions

What is CVE-2018-4878?: CVE-2018-4878 is a high-severity vulnerability in Adobe Flash Player, classified under Use After Free. CVSS score: 7.8/10. Published 2018-02-06.
How severe is CVE-2018-4878?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2018-4878 known to be exploited?: Yes. CVE-2018-4878 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03), indicating it is being actively exploited. 131 public proof-of-concept repositories are indexed.