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.
- CVSS
- 7.8Highscored by CISA
- Exploited in the wild
- Yes, in CISA KEV since 3 Nov 2021CISA deadline for US federal agencies: 3 May 2022known use in ransomware campaignspublic exploit code
- EPSS
- 90.3%chance of exploitation in the next 30 daystop 0.2% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Patch availablesee the advisories in the references
- Published
- 6 Feb 2018analysed here 12 Nov 2026
Do first. The impacted product is end-of-life and should be disconnected if still in use. (CISA's required action for this KEV entry)
Summary
Triage
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
| Product | Affected versions | Vendor says fixed in |
|---|---|---|
| Adobe Flash Player before 28.0.0.161 | Adobe Flash Player before 28.0.0.161Vendor says fixed in: not stated |
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.
Products named in our analysis
- adobe:flash_player
- redhat:enterprise_linux_desktop
- redhat:enterprise_linux_server
- redhat:enterprise_linux_workstation
Fix and mitigation
WAF and other mitigations
Can a WAF block it? No. The attack needs local access to the machine, so a WAF is not on its path.
Also consider: patch
Based on the attack vector (local or physical access). We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Listed since 3 Nov 2021. Known use in ransomware campaigns.
- CISA due date
- 3 May 2022, the remediation deadline for US federal agencies
- CISA required action
- The impacted product is end-of-life and should be disconnected if still in use.
- Public exploit code
- Yes: 3 on Exploit-DB · 10 GitHub proofs of concept
- CISA SSVC
- exploitation active, automatable no, technical impact totalAssessed by CISA 17 Nov 2025 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
Exploit-DB
- Adobe Flash < 28.0.0.161 - Use-After-Freeremote, 6 Apr 2018
- Flash ActiveX 28.0.0.137 - Code Execution (1)local, 16 Feb 2016
- Flash ActiveX 28.0.0.137 - Code Execution (2)local, 13 Feb 2016
GitHub proofs of concept
- vysecurity/CVE-2018-487886 stars
- SyFi/CVE-2018-48787 stars
- B0fH/CVE-2018-48782 stars
- ydl555/CVE-2018-4878-1 stars
and 6 more repositories
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
Timeline
- 13 Feb 2016First public exploit or proof of concept
- 6 Feb 2018Published725 days (about 2 years) later
- 3 Nov 2021Added to CISA KEV (exploited in the wild)1,365 days (about 4 years) later
- 3 May 2022CISA remediation due date (US federal agencies)181 days (about 6 months) later
- 17 Nov 2025CISA SSVC assessment: exploitation active1,295 days (about 4 years) later
- 17 Nov 2025CVE record last updatedsame day later
- 12 Nov 2026Analysed by vulneraibility.com360 days (about 12 months) later
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
| Metric | Value | What it means |
|---|---|---|
| Attack vector | LocalLocal access required (shell, logged-in user). | Local access required (shell, logged-in user). |
| Attack complexity | LowRepeatable attack, no special conditions. | Repeatable attack, no special conditions. |
| Privileges required | NoneThe attacker needs no prior access. | The attacker needs no prior access. |
| User interaction | RequiredA victim must click, open or otherwise cooperate. | A victim must click, open or otherwise cooperate. |
| Scope | UnchangedImpact stays within the vulnerable component. | Impact stays within the vulnerable component. |
| Confidentiality | HighTotal data disclosure possible. | Total data disclosure possible. |
| Integrity | HighComplete modification possible. | Complete modification possible. |
| Availability | HighFull outage possible. | Full outage possible. |
Common questions
Is CVE-2018-4878 being exploited?
Yes. CVE-2018-4878 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2018-4878?
CVE-2018-4878 is rated High with a CVSS score of 7.8. 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-2018-4878?
Yes. A fix has been recorded for CVE-2018-4878. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2018-4878 affect?
CVE-2018-4878 affects adobe:flash_player, redhat:enterprise_linux_desktop, redhat:enterprise_linux_server, redhat:enterprise_linux_workstation. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
16 references in the CVE record, grouped by the tags the record gives them.
Advisories (1)
- access.redhat.com /errata/RHSA-2018:0285
Exploits (1)
- exploit-db.com /exploits/44412/
Other links (14)
- blog.talosintelligence.com /2018/02/group-123-goes-wild.html
- threatpost.com /adobe-flash-player-zero-day-spotted-in-the-wild/129742/
- helpx.adobe.com /security/products/flash-player/apsb18-03.html
- securitytracker.com /id/1040318
- securityfocus.com /bid/102893
- fireeye.com /blog/threat-research/2018/02/attacks-leveraging-adobe-zero-day.html
Show 8 more
- blog.morphisec.com /flash-exploit-cve-2018-4878-spotted-in-the-wild-massive-malspam-campaign
- darkreading.com /threat-intelligence/adobe-flash-vulnerability-reappears-in-malicious-word-files
- github.com /InQuest/malware-samples/tree/master/CVE-2018-4878-Adobe-Flash-DRM-UAF-0day
- trendmicro.com /vinfo/us/security/news/vulnerabilities-and-exploits/north-korean-hackers-allege
- github.com /vysec/CVE-2018-4878
- securingtomorrow.mcafee.com /mcafee-labs/hackers-bypassed-adobe-flash-protection-mechanism/
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-4878
- github.com /cisagov/vulnrichment/issues/196
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Exploit-DB: published exploits
- PoC-in-GitHub: GitHub repositories that claim a proof of concept
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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