CVE-2015-1671
Microsoft Windows · Operating systems
Microsoft Windows Remote Code Execution Vulnerability
At a glance
Exploited. Added to CISA’s catalog of exploited vulnerabilities on May 25, 2022.
Affected product: Microsoft Windows (category Operating systems, indicative classification). Name in CISA’s catalog: Microsoft Windows.
What should I do?
Apply the security update from Microsoft.
Deadline set by CISA for US federal agencies: 21 days (due June 15, 2022). It only binds those agencies, but it is a useful measure of urgency.
- CVE-2015-1671 in Microsoft’s Security Update Guide
- Microsoft security advisories page (general page, not the advisory for this vulnerability)
- The vendor’s specific advisory is listed in the NVD references: CVE-2015-1671 on the NVD website.
Original text of the required action (CISA)
Apply updates per vendor instructions.
Timeline
- Vulnerability published Publication date (NVD)
- Exploitation confirmed Added to CISA’s KEV catalog
- CISA deadline Remediation deadline set for US federal agencies
The facts, with their sources
- Exploitation confirmed
- Yes, on May 25, 2022 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Ransomware
- No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Hunt for compromise
- Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CISA required action
- Apply the security update from Microsoft. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CISA deadline
- June 15, 2022, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Microsoft patch
- Not available Source: Security Update Guide, collected September 29, 2026 at 14:57 UTC
- Vulnerability published
- May 13, 2015 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
- Product according to CISA
- Microsoft Windows Filed by this site under “Operating systems” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Severity and activity
Score from the vendor or CISA, relayed by the NVD. Collected Sep 29, 2026.
FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.
Description
The Windows DirectWrite library, as used in Microsoft .NET Framework 3.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2; Office 2007 SP3 and 2010 SP2; Live Meeting 2007 Console; Lync 2010; Lync 2010 Attendee; Lync 2013 SP1; Lync Basic 2013 SP1; Silverlight 5 before 5.1.40416.00; and Silverlight 5 Developer Runtime before 5.1.40416.00, allows remote attackers to execute arbitrary code via a crafted TrueType font, aka "TrueType Font Parsing Vulnerability."
Official description from the NVD, collected Sep 29, 2026. CVE® description © The MITRE Corporation.
A remote code execution vulnerability exists when components of Windows, .NET Framework, Office, Lync, and Silverlight fail to properly handle TrueType fonts.
Summary from CISA (KEV catalog).
CERT-FR advisories
No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.
Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.
Sources for this page
- CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
- Microsoft Security Update Guide: product, patch.
- NVD (NIST): CVSS severity, publication date, description, vendor references.
- EPSS (FIRST): probability of exploitation.
- CERT-FR: advisories and alerts (in French).
- Brand and category: indicative classification by this site (method).