CVE-2021-41093Network attack vector

Account takeover via short-lived token email change

Published Oct 4, 2021 · Updated Aug 4, 2024

Improper authorization in Wire iOS before 3.86 allows remote attackers with an old valid access token to take over an account. The client sends an email-change request to the /self/email endpoint using only the short-lived token in the Authorization header, without the long-lived authentication cookie. Possession of an old but still valid token is required; changing the account email transfers control of the account.

CVSS severity7.4
High
EPSS probability1.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Wire iOS before 3.86 allows remote attackers with an old valid access token to take over an account. The client sends an email-change request to the /self/email endpoint using only the short-lived token in the Authorization header, without the long-lived authentication cookie. Possession of an old but still valid token is required; changing the account email transfers control of the account.

The record

CVE
CVE-2021-41093
Published
Oct 4, 2021
Updated
Aug 4, 2024
Vendor
Wire Swiss GmbH
Product
Wire iOS
Classifications
CWE-863, CWE-285, T1078
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 4, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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=< 3.86

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Wire Swiss GmbH · Wire iOSversion=< 3.86

Published CVSS scores

9.8NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.4GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
7.5NIST National Vulnerability DatabaseAV:N/AC:L/Au:N/C:P/I:P/A:P

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-863Incorrect Authorization
CWE-285Improper Authorization
T1078Valid Accounts

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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