Patchfirst
CVE-2022-39197 KEVPublic exploit Medium · 6.1 EPSS 44.1%

Fortra Cobalt Strike Teamserver Cross-Site Scripting (XSS) Vulnerability

Fortra · Cobalt Strike

Summary

A cross-site scripting flaw in Fortra's Cobalt Strike teamserver, present in HelpSystems Cobalt Strike through version 4.7, lets a remote attacker inject HTML into the teamserver's interface via the username field of a payload. Exploitation requires that the attacker first inspect a Cobalt Strike payload and then modify its username field (or generate a new payload with the extracted information and alter that field to be malformed), with the attacker needing no authentication but requiring a user to interact with the crafted content.

Official description · NVD

An XSS (Cross Site Scripting) vulnerability was found in HelpSystems Cobalt Strike through 4.7 that allowed a remote attacker to execute HTML on the Cobalt Strike teamserver. To exploit the vulnerability, one must first inspect a Cobalt Strike payload, and then modify the username field in the payload (or create a new payload with the extracted information and then modify that username field to be malformed).

Breakdown
70.9 / 100
Exploited
Yes, in CISA KEV
Reports
1
Tactics
1/15

How an attack unfolds

Based on mappings. Select a step to see the evidence.
  1. What they do

First seen exploited 4 months after disclosure. Public exploit code (PoC-in-GitHub) was available 1 day before disclosure.

  1. Public exploit codePoC-in-GitHub1 day before
  2. Disclosedday 0
  3. First seen exploitedVulnCheck KEV evidence+4 mo
  4. Added to CISA KEVEU database agrees+6 mo

CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.

techniques

1 , grouped by in kill-chain order 1

ExecutionTA0002

MITRE CTID mapping of the KEV entry · primary impact

This vulnerability is exploited by a remote attacker to execute HTML on the Cobalt Strike team server. To exploit this vulnerability, an attacker would inspect a Cobalt Strike payload and modify the username field within the payload to be malformed. This manipulation enables the attacker to execute arbitrary code by setting a malformed username in the Beacon configuration. In a documented cybersecurity incident, a Chinese threat actor leveraged a modified version of Cobalt Strike, known as "Cobalt Strike Cat," which included a patch for CVE-2022-39197. This version was used to establish communication channels with victim systems, perform evasive post-exploitation activities, and maintain persistence.

Lower-confidence links (1)

These come from early or generic mappings, text matching, or contradict this CVE’s details (for example a public-facing technique on a bug that needs a user to open a file). Shown for completeness.

  • Exploit Public-Facing ApplicationT1190 needs user interaction; not a public-facing exploit

Detection

0 rules for this CVE · 95 general rules for its techniques

Rules for this CVE

0 that reference CVE-2022-39197 directly.

CVE-specific rules are not available in this build. Search SigmaHQ ↗

General rules for this CVE’s techniques

These detect the technique in general, not this specific vulnerability.

Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.

What security researchers reported

Named in 1 threat report
1 reportEclecticIQ

Reports are matched by finding the exact id CVE-2022-39197 in their text; nobody has reviewed the match. One passage is shown per report, at most 320 characters, linked to the original.

Also mentioned in 50 community threat pulses (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

References

3 links, grouped by NVD tag (2 duplicates merged)
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