CVE-2021-22912Public exploitNetwork attack vector

Sharee-search disclosure via default lookup-server queries

Published Jun 11, 2021 · Updated Aug 3, 2024

Information disclosure in Nextcloud iOS before 3.4.2 allows attackers to obtain sharee searches through the lookup server. The client routes ordinary sharee searches to the lookup server by default instead of limiting them to the configured local Nextcloud server. A signed-in user must perform a sharee search; the disclosure is limited to search data sent to the lookup service.

CVSS severity6.5
Medium
EPSS probability1.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Nextcloud iOS before 3.4.2 allows attackers to obtain sharee searches through the lookup server. The client routes ordinary sharee searches to the lookup server by default instead of limiting them to the configured local Nextcloud server. A signed-in user must perform a sharee search; the disclosure is limited to search data sent to the lookup service.

The record

CVE
CVE-2021-22912
Published
Jun 11, 2021
Updated
Aug 3, 2024
Vendor
Nextcloud GmbH
Product
Nextcloud iOS Client
Classifications
CWE-201, CWE-200
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Fixed in 3.4.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Nextcloud GmbH · Nextcloud iOS Clientversion=Fixed in 3.4.2

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
4.3NIST NVDAV:N/AC:M/Au:N/C:P/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-201Insertion of Sensitive Information Into Sent Data
CWE-200Exposure of Sensitive Information to an Unauthorized Actor

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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