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NVD / CVE Program· CNA apache

CVE-2021-27576: Apache OpenMeetings: bandwidth can be overloaded with public web service

HighCVSS 7.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 31/100)

  • 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: 2.8% (FIRST EPSS); higher than 86.8% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: org.apache.openmeetings:openmeetings-parent (Maven) 6.0.0.

Low priority for now. Upgrade to org.apache.openmeetings:openmeetings-parent (Maven) 6.0.0 or later.

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

If was found that the NetTest web service can be used to overload the bandwidth of a Apache OpenMeetings server. This issue was addressed in Apache OpenMeetings 6.0.0

Published
Mar 15, 2021
Updated
Jun 16, 2026
EPSS
2.8% · 86th percentile
CWE
—

Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 2.8%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-27576

When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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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.

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Affected 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.

VendorProduct
apacheopenmeetings

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apache). Independent of NVD's CPE analysis and usually ahead of it.

  • Apache Software Foundation Apache OpenMeetings

    • 4.0.0 and later · before Apache OpenMeetings 4*affected
    • Apache OpenMeetings 5 and later · up to and including 5.1.0affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apache openmeetings4.0.0 and later · before 6.0.0

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Mavenorg.apache.openmeetings:openmeetings-parentfrom 4.0.0 · before 6.0.06.0.0

Same product

apache: all records

Other highest-scoring records for the same primary product.

  • CVE-2024-54676Apache OpenMeetings: Deserialisation of untrusted data in cluster mode
    60This week
  • CVE-2020-13951Attackers can use public NetTest web service of Apache OpenMeetings 4.0.0-5.0.0 to organize denial of service attack.
    51Plan
  • CVE-2016-0784Directory traversal vulnerability in the Import/Export System Backups functionality in Apache OpenMeetings before 3.1.1 allows remote…
    42Plan

Published before and after this one in the same product

  • ← EarlierCVE-2016-8736Oct 12, 2017 · Apache OpenMeetings before 3.1.2 is vulnerable to Remote Code Execution via RMI deserialization attack.
    40Plan
  • ← EarlierCVE-2018-1286Feb 28, 2018 · In Apache OpenMeetings 3.0.0 - 4.0.1, CRUD operations on privileged users are not password protected allowing an authenticated attacker to…
    26Monitor
  • Later →CVE-2023-28326Mar 28, 2023 · Apache OpenMeetings: allows user impersonation
    39Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Maven:org.apache.openmeetings:openmeetings-parent6.0.0Package registry (OSV)

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.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Not on record for this CVE: EPSS history · patch commit or PR link · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

—

CVSS vector

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

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records