CVE-2008-3873: The System.setClipboard method in ActionScript in Adobe Flash Player 9.0.124.0 and earlier allows remote attackers to…

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of 29 Oct 2026.

VulnCheck KEV lists it since 29 Aug 2008. It cites 2 public reports, the first from 29 Aug 2008.

• nvd.nist.gov
• cve.org

How likely is exploitation in the next 30 days?

17%

EPSS score, percentile 97.1 of all scored records. A probability estimated by FIRST, not a report of exploitation.

How severe?

Not scored

The CVE record carries no CVSS score.

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

Advisories and patches (5)

Which versions are affected?

Not stated. The CVE record gives vendor and product as “n/a” and the version as “unspecified”.

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; VulnCheck KEV, as of 30 Oct 2026; FIRST EPSS, as of 29 Oct 2026; CVE List, as of 30 Oct 2026. About the data.

Description

The System.setClipboard method in ActionScript in Adobe Flash Player 9.0.124.0 and earlier allows remote attackers to populate the clipboard with a URL that is difficult to delete and does not require user interaction to populate the clipboard, as exploited in the wild in August 2008.

Source: CVE List, as of 30 Oct 2026. About the data.

What to do

Advisories and patches

• GLSA-200903-23 (Vendor advisory)
• RHSA-2008:0945 (Vendor advisory)
• RHSA-2008:0980 (Vendor advisory)
• 248586 (Vendor advisory)
• SUSE-SR:2008:025 (Vendor advisory)

This summary is based on the CVE record as of 30 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

The CVE record does not name affected products or versions: vendor and product are “n/a” and the version is “unspecified”.

Source: CVE List, as of 30 Oct 2026. About the data.

Timeline