Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2021-20838

25
FAUCET Score

CVE-2021-20838 describes an XML External Entity (XXE) vulnerability in Antenna House Office Server Document Converter versions V7.2MR4 and earlier, and V7.1MR7 and earlier. This flaw allows an unauthenticated remote attacker to trigger a denial of service (DoS) condition by submitting a specially crafted XML document. With a CVSS score of 7.5 (High), the attack requires no user interaction and has low complexity, making it a significant availability risk. There is currently no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage surrounding this vulnerability.

Impacted Technologies

VendorProductVersion(s)CPE
< 5.2CPE matchmatch criteria
cpe:2.3:a:antennahouse:office_server_document_converter:*:*:*:*:*:*:*:*
5.2CPE matchmatch criteria
cpe:2.3:a:antennahouse:office_server_document_converter:5.2:-:*:*:*:*:*:*
6.0CPE matchmatch criteria
cpe:2.3:a:antennahouse:office_server_document_converter:6.0:-:*:*:*:*:*:*
6.0CPE matchmatch criteria
cpe:2.3:a:antennahouse:office_server_document_converter:6.0:mr1:*:*:*:*:*:*
6.0CPE matchmatch criteria
cpe:2.3:a:antennahouse:office_server_document_converter:6.0:mr2:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

7.5HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
3.6
CvssVersion
3.1

Exploit Intelligence

EPSS Score
1.47%
Probability of exploitation in next 30 days
EPSS Percentile
71.1%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0147 is in the 52nd percentile among its peer group of 51,506 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Remediation records are not available for this CVE.

References

jvn.jp / en/jp/JVN33453839/index.html
Third Party Advisory
antenna.co.jp / news/2021/osdc72-20211027.html
PatchVendor Advisory