CVE-2020-26085Network attack vector

Program execution via improperly validated XMPP messages

Published Jan 6, 2021 · Updated Nov 12, 2024

Improper message validation in Cisco Jabber for Windows and MacOS allows remote authenticated users to execute local programs via XMPP. The client accepts crafted XMPP message content that names an executable already present in its local application path and launches it with the Jabber user's privileges. The attacker needs a route to send XMPP messages; phone-only and non-XMPP messaging configurations are not exposed.

CVSS severity9.9
Critical
EPSS probability2.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper message validation in Cisco Jabber for Windows and MacOS allows remote authenticated users to execute local programs via XMPP. The client accepts crafted XMPP message content that names an executable already present in its local application path and launches it with the Jabber user's privileges. The attacker needs a route to send XMPP messages; phone-only and non-XMPP messaging configurations are not exposed.

The record

CVE
CVE-2020-26085
Published
Jan 6, 2021
Updated
Nov 12, 2024
Vendor
ClamAV
Product
Cisco Jabber
Classifications
CWE-201, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 6, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 12, 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=n/a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ClamAV · Cisco Jabberversion=n/a

Published CVSS scores

9.9CiscoCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-201Insertion of Sensitive Information Into Sent Data
T1203Exploitation for Client Execution

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

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Your stack

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