CVE-2021-1417Network attack vector

Sensitive information disclosure via crafted XMPP message

Published Mar 24, 2021 · Updated Nov 8, 2024

Information disclosure in Cisco Jabber for Windows allows remote authenticated users to obtain sensitive authentication information via crafted XMPP messages. Improper validation of XMPP message content causes the client to return authentication data to another system. Exploitation requires an authenticated XMPP account able to send messages to the target, and the documented consequence is confidentiality loss without integrity or availability impact.

CVSS severity6.5
Medium
EPSS probability0.96%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Information disclosure in Cisco Jabber for Windows allows remote authenticated users to obtain sensitive authentication information via crafted XMPP messages. Improper validation of XMPP message content causes the client to return authentication data to another system. Exploitation requires an authenticated XMPP account able to send messages to the target, and the documented consequence is confidentiality loss without integrity or availability impact.

The record

CVE
CVE-2021-1417
Published
Mar 24, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco Jabber
Classifications
CWE-170, T1041
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 24, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ClamAV · Cisco Jabberversion=n/a

Published CVSS scores

6.5NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
6.5CiscoCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-170Improper Null Termination
T1041Exfiltration Over C2 Channel

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo