CVE-2021-34421Network attack vector

Sensitive-data disclosure via incomplete exploded-message cleanup

Published Nov 11, 2021 · Updated Sep 17, 2024

Incomplete cleanup in Keybase Client for Android and iOS before 5.8.0 allows remote attackers to cause disclosure of exploded messages. When a recipient backgrounds the chat while the sender explodes a message, the clients fail to remove that message from the recipient device. The sender must time deletion to the backgrounded session; the documented consequence is persistence of data intended for deletion.

CVSS severity3.7
Low
EPSS probability0.71%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incomplete cleanup in Keybase Client for Android and iOS before 5.8.0 allows remote attackers to cause disclosure of exploded messages. When a recipient backgrounds the chat while the sender explodes a message, the clients fail to remove that message from the recipient device. The sender must time deletion to the backgrounded session; the documented consequence is persistence of data intended for deletion.

The record

CVE
CVE-2021-34421
Published
Nov 11, 2021
Updated
Sep 17, 2024
Vendor
Zoom Video Communications, Inc.
Product
Keybase Client for iOS
Classifications
CWE-459
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=unspecified <5.8.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Zoom Video Communications, Inc. · Keybase Client for iOSversion=unspecified <5.8.0
Zoom Video Communications, Inc. · Keybase Client for Androidversion=unspecified <5.8.0

Published CVSS scores

3.7Zoom Video Communications, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
4.3NIST National Vulnerability DatabaseAV:N/AC:M/Au:N/C:P/I:N/A:N
4.3NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-459Incomplete Cleanup

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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