CVE-2020-1020: Microsoft Windows Adobe Font Manager Library Remote Code Execution Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on , 567 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 65%
EPSS score, percentile 99.2 of all scored records
- How severe?
- 8.8 High
CVSS v3.1 base score, from CISA's enrichment of the record
- What should I do?
CISA deadline . Apply updates per vendor instructions.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 10 Version 1803 for 32-bit Systems
- 10 Version 1803 for x64-based Systems
- 10 Version 1803 for ARM64-based Systems
- 10 Version 1809 for 32-bit Systems
- 10 Version 1809 for x64-based Systems
- 10 Version 1809 for ARM64-based Systems
and 26 more in the table below
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
What to do
Required action, set by CISA
Apply updates per vendor instructions.
CISA due date for this action: .
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 10 Version 1803 for 32-bit Systems |
| Affected | 10 Version 1803 for x64-based Systems |
| Affected | 10 Version 1803 for ARM64-based Systems |
| Affected | 10 Version 1809 for 32-bit Systems |
| Affected | 10 Version 1809 for x64-based Systems |
| Affected | 10 Version 1809 for ARM64-based Systems |
| Affected | 10 Version 1709 for 32-bit Systems |
| Affected | 10 Version 1709 for x64-based Systems |
| Affected | 10 Version 1709 for ARM64-based Systems |
| Affected | 10 for 32-bit Systems |
| Affected | 10 for x64-based Systems |
| Affected | 10 Version 1607 for 32-bit Systems |
And 6 more version entries in the CVE record.
| Status | Versions |
|---|---|
| Affected | version 1803 (Core Installation) |
| Affected | 2019 |
| Affected | 2019 (Core installation) |
| Affected | 2016 |
| Affected | 2016 (Core installation) |
| Affected | 2008 for 32-bit Systems Service Pack 2 |
| Affected | 2008 for 32-bit Systems Service Pack 2 (Core installation) |
| Affected | 2008 for Itanium-Based Systems Service Pack 2 |
| Affected | 2008 for x64-based Systems Service Pack 2 |
| Affected | 2008 for x64-based Systems Service Pack 2 (Core installation) |
| Affected | 2008 R2 for Itanium-Based Systems Service Pack 1 |
| Affected | 2008 R2 for x64-based Systems Service Pack 1 |
And 5 more version entries in the CVE record.
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
About this vulnerability
Microsoft Windows Adobe Font Manager Library contains an unspecified vulnerability when handling specially crafted multi-master fonts (Adobe Type 1 PostScript format) that allows for remote code execution for all systems except Windows 10. For systems running Windows 10, an attacker who successfully exploited the vulnerability could execute code in an AppContainer sandbox context with limited privileges and capabilities.
Summary: CISA's KEV catalog, as of .
- CISA added CVE-2020-1020 to its Known Exploited Vulnerabilities (KEV) catalog on 3 Nov 2021.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 3 May 2022.
- The CVE record was published on 15 Apr 2020, 567 days before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 8.8 (High), taken from CISA's enrichment of the record.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 65% (percentile 99.2), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of . About the data.
Description
A remote code execution vulnerability exists in Microsoft Windows when the Windows Adobe Type Manager Library improperly handles a specially-crafted multi-master font - Adobe Type 1 PostScript format.For all systems except Windows 10, an attacker who successfully exploited the vulnerability could execute code remotely, aka 'Adobe Font Manager Library Remote Code Execution Vulnerability'. This CVE ID is unique from CVE-2020-0938.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
Weakness
- CWE-787: Out-of-bounds Write
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| Added to CISA KEV | |
| CISA due date for the required action | |
| CVE record last updated |
References
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