CVE-2021-21045: Acrobat Reader DC Improper Installer Access Control Vulnerability Could Lead To Privilege Escalation
Noroxi assessment
Priority: Monitor (action score 33/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 1.7% (FIRST EPSS); higher than 77.9% of all records.
- Someone with local access to the system can trigger it. A low-privileged account is enough. A user must open a link or visit a page. No special conditions are required; it is repeatable.
- According to the record, no fixed version is available yet.
Low priority for now. Update when a fix is released; follow the vendor's advisory.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Acrobat Reader DC versions versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier) and 2017.011.30188 (and earlier) are affected by an improper access control vulnerability. An unauthenticated attacker could leverage this vulnerability to elevate privileges in the context of the current user.
- Published
- Feb 11, 2021
- Updated
- Jun 16, 2026
- EPSS
- 1.7% · 77th percentile
- CWE
- CWE-284
Report tools
Action score
33
Monitor
Low priority for now.
- CVSS
- 32 / 40 · 8.2 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 1.7%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · adobe
- 8.2
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- No fixed version yet
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| adobe | acrobat | cpe:2.3:a:adobe:acrobat |
| adobe | acrobat dc | cpe:2.3:a:adobe:acrobat_dc |
| adobe | acrobat reader | cpe:2.3:a:adobe:acrobat_reader |
| adobe | acrobat reader dc | cpe:2.3:a:adobe:acrobat_reader_dc |
| apple | macos | cpe:2.3:o:apple:macos |
| microsoft | windows | cpe:2.3:o:microsoft:windows |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- adobe acrobat17.0 and later · up to 17.011.30188 inclusive
- adobe acrobat20.0 and later · up to 20.001.30018 inclusive
- adobe acrobat dcup to 20.013.20074 inclusive
- adobe acrobat reader17.0 and later · up to 17.011.30188 inclusive
- adobe acrobat reader20.0 and later · up to 20.001.300183 inclusive
- adobe acrobat reader dcup to 20.013.20074 inclusive
Versions reported by the vendor
Affected version ranges reported by the assigning authority (adobe). Independent of NVD's CPE analysis and usually ahead of it.
Adobe Acrobat Reader
- unspecified and later · up to and including 2020.013.20074affected
- unspecified and later · up to and including 2020.001.30018affected
- unspecified and later · up to and including 2017.011.30188affected
- unspecified and later · up to and including Noneaffected
Same product
adobe: all recordsOther highest-scoring records for the same primary product.
- CVE-2011-2462Unspecified vulnerability in the U3D component in Adobe Reader and Acrobat 10.1.1 and earlier on Windows and Mac OS X, and Adobe Reader 9.x KEV96Now
- CVE-2013-3346Adobe Reader and Acrobat 9.x before 9.5.5, 10.x before 10.1.7, and 11.x before 11.0.03 allow attackers to execute arbitrary code or cause a KEV93Now
- CVE-2021-21017Acrobat Reader DC Heap-based Buffer Overflow Vulnerability Could Lead To Arbitrary Code ExecutionKEV91Now
Published before and after this one in the same product
- ← EarlierCVE-2021-21042Feb 11, 2021 · Acrobat Reader DC Out-Of-Bounds Read Information Disclosure Vulnerability30Monitor
- ← EarlierCVE-2021-21044Feb 11, 2021 · Acrobat Reader DC Out-Of-Bounds Write Vulnerability Could Lead To Arbitrary Code Execution32Monitor
- Later →CVE-2021-21046Feb 11, 2021 · Acrobat Reader DC Buffer Overflow Vulnerability Could Lead To Arbitrary Code Execution14Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- Required
- Scope
- Changed
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-284 · Improper Access ControlCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Embedding Scripts within ScriptsCAPEC-19likelihood: High · High
- Malicious Logic InsertionCAPEC-441likelihood: Medium · High
- Modification of Windows Service ConfigurationCAPEC-478likelihood: Low · High
- Malicious Root CertificateCAPEC-479likelihood: Low · Low
- Intent SpoofCAPEC-502
- WebView ExposureCAPEC-503
- Data Injected During ConfigurationCAPEC-536likelihood: Low · High
- Incomplete Data Deletion in a Multi-Tenant EnvironmentCAPEC-546likelihood: Low · Medium
ATT&CK techniques
- RootkitT1014
- Obfuscated Files or Information: Embedded PayloadsT1027.009
- Boot or Logon Initialization ScriptsT1037
- Taint shared contentT1080
- Server Software Component: Terminal Services DLLT1505.005
- Pre-OS Boot:BootkitT1542.003
- Create or Modify System ProcessT1543
- Create or Modify System Process: Launch AgentT1543.001
- Create or Modify System Process:Windows ServiceT1543.003
- Create or Modify System Process: Launch DaemonT1543.004
- Event Triggered Execution:Change Default File AssociationT1546.001
- Event Triggered Execution:.bash_profile and .bashrcT1546.004
- Event Triggered Execution: Accessibility FeaturesT1546.008
- Event Triggered Execution: Installer PackagesT1546.016
- Boot or Logon Autostart ExecutionT1547
- Boot or Logon Autostart Execution:Kernel Modules and ExtensionsT1547.006
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.