How to Fix CVE-2026-30847: Information exposure in Wekan
By Sai Kiran Pandrala. Last verified: 2026-05-25.
CVE-2026-30847 is a information exposure in Wekan Wekan. The fix is to apply the vendor patch noted below.
| Severity | 9.3 (Critical) |
|---|---|
| Actively exploited? | No public listing in CISA KEV |
| Affected | Wekan >= 8.31.0, < 8.34 |
| Fixed in | See vendor advisory |
| Type (CWE) | CWE-200: Exposure of Sensitive Information to an Unauthorized Actor |
What is CVE-2026-30847?
Wekan is an open source kanban tool built with Meteor. In versions 8.31.0 through 8.33, the notificationUsers publication in Wekan publishes user documents with no field filtering, causing the ReactiveCache.getUsers() call to return all fields including highly sensitive data such as bcrypt password hashes, active session login tokens, email verification tokens, full email addresses, and any stored OAuth tokens. Unlike Meteor's default auto-publication which strips the services field for security, custom publications return whatever fields the cursor contains, meaning all subscribers receive the complete user documents. Any authenticated user who triggers this publication can harvest credentials and active session tokens for other users, enabling password cracking, session hijacking, and full account takeover. This issue has been fixed in version 8.34. The CVSS base score is 9.3 (Critical), which puts this in the upper risk band and warrants a fast patch cycle. The official advisory is at https://securitylab.github.com/advisories/GHSL-2026-035_Wekan/.
Am I affected?
Check the version of Wekan you are running and compare it against the Affected row above (Wekan >= 8.31.0, < 8.34). If your build sits inside the affected range, you must patch.
Run the version check that fits your platform:
# Linux package check
dpkg -s wekan 2>/dev/null | grep -i ^Version
rpm -q wekan 2>/dev/null
command -v wekan >/dev/null && wekan --version 2>/dev/null
# Windows (PowerShell)
Get-Package -Name "*Wekan*" -ErrorAction SilentlyContinue | Select-Object Name, Version
winget list --name "Wekan" 2>$null
How to fix CVE-2026-30847
Upgrade Wekan to a patched build: See vendor advisory. The vendor advisory is the source of truth for the exact fixed version.
Ubuntu / Debian
sudo apt-get update
sudo apt-get install --only-upgrade wekan
dpkg -s wekan | grep -i ^Version
RHEL / CentOS / Rocky / AlmaLinux
sudo dnf upgrade --refresh wekan -y
# or for older releases:
sudo yum update wekan -y
rpm -q wekan
SUSE / openSUSE
sudo zypper refresh
sudo zypper update wekan
rpm -q wekan
Complete PowerShell remediation script (Windows)
# Fix script for CVE-2026-30847 affecting Wekan
# Run as administrator. Detect -> backup -> upgrade -> verify -> log.
$ErrorActionPreference = "Stop"
$LogPath = "C:\Logs\CVE-2026-30847-fix-$(Get-Date -Format yyyyMMdd-HHmmss).log"
New-Item -ItemType Directory -Force (Split-Path $LogPath) | Out-Null
Start-Transcript -Path $LogPath -Append
try {
Write-Host "[1/4] Detect installed version"
$pkg = Get-Package -Name "*Wekan*" -ErrorAction SilentlyContinue
if ($pkg) { $pkg | Format-Table Name, Version }
else { Write-Host "Not detected via Get-Package; try winget list" }
Write-Host "[2/4] Backup configuration"
$backup = "C:\Backup\wekan-$(Get-Date -Format yyyyMMdd)"
New-Item -ItemType Directory -Force $backup | Out-Null
Get-ChildItem "C:\ProgramData\Wekan" -ErrorAction SilentlyContinue |
Copy-Item -Destination $backup -Recurse -Force -ErrorAction SilentlyContinue
Write-Host "[3/4] Apply the upgrade to See vendor advisory"
winget upgrade --name "Wekan" --silent --accept-source-agreements --accept-package-agreements
if ($LASTEXITCODE -ne 0) {
# Fallback: pull latest via OS update channel
Install-Module -Name PSWindowsUpdate -Force -SkipPublisherCheck -ErrorAction SilentlyContinue
Import-Module PSWindowsUpdate
Install-WindowsUpdate -MicrosoftUpdate -AcceptAll -IgnoreReboot
}
Write-Host "[4/4] Verify the patched build"
winget list --name "Wekan"
Write-Host "Patch applied. Reboot if prompted."
exit 0
} catch {
Write-Error "Patch failed: $_"
exit 1
} finally {
Stop-Transcript
}
Complete Bash remediation script (Linux)
#!/usr/bin/env bash
# Fix script for CVE-2026-30847 affecting Wekan
# Detect -> backup -> upgrade -> verify -> log.
set -euo pipefail
LOG="/var/log/cve-2026-30847-fix-$(date +%Y%m%d-%H%M%S).log"
exec > >(tee -a "$LOG") 2>&1
echo "[1/4] Detect installed version"
if command -v dpkg >/dev/null; then
dpkg -s wekan 2>/dev/null | grep -i ^Version || echo "wekan not installed via dpkg"
elif command -v rpm >/dev/null; then
rpm -q wekan || echo "wekan not installed via rpm"
fi
echo "[2/4] Backup configuration"
BACKUP="/root/backup-cve-2026-30847-$(date +%Y%m%d)"
mkdir -p "$BACKUP"
for d in /etc/wekan /etc/wekan.d /etc/wekan.conf; do
[ -e "$d" ] && cp -a "$d" "$BACKUP/" || true
done
echo "[3/4] Apply the upgrade (target: See vendor advisory)"
if command -v apt-get >/dev/null; then
apt-get update
apt-get install --only-upgrade -y wekan
elif command -v dnf >/dev/null; then
dnf upgrade --refresh -y wekan
elif command -v yum >/dev/null; then
yum update -y wekan
elif command -v zypper >/dev/null; then
zypper --non-interactive update wekan
fi
echo "[4/4] Verify the patched build"
if command -v dpkg >/dev/null; then
dpkg -s wekan 2>/dev/null | grep -i ^Version
elif command -v rpm >/dev/null; then
rpm -q wekan
fi
echo "Done. Restart any service that loaded the old library."
If you can't patch immediately
Apply at least one of the following inline controls until you can deploy the patched build. None replace the upgrade.
Restrict exposure with nftables (Linux)
# Allow only trusted CIDR to reach the affected service ports
sudo nft add table inet filter 2>/dev/null || true
sudo nft 'add chain inet filter input { type filter hook input priority 0 ; }' 2>/dev/null || true
sudo nft 'add rule inet filter input tcp dport {80, 443} ip saddr != 10.0.0.0/8 drop'
sudo nft list ruleset
Block at the host firewall (Windows)
New-NetFirewallRule -DisplayName "Block-CVE-2026-30847" -Direction Inbound -Action Block -Protocol TCP -LocalPort 80,443 -RemoteAddress Any -Enabled True
Get-NetFirewallRule -DisplayName "Block-CVE-2026-30847"
Disable the affected service (Linux)
sudo systemctl stop wekan 2>/dev/null || true
sudo systemctl disable wekan 2>/dev/null || true
If the vendor advisory lists an official workaround, prefer that wording verbatim. If no workaround is published, the only safe remediation is the patch.
How to verify the fix worked
After upgrading, confirm the installed version matches the patched build and that no old library is still loaded by a long-running process.
# Linux
dpkg -s wekan 2>/dev/null | grep -i ^Version
rpm -q wekan 2>/dev/null || true
# Pid map check for old library handles
sudo lsof +c0 2>/dev/null | grep -i "DEL.*lib" || true
# Windows
Get-Package -Name "*Wekan*" | Select-Object Name, Version
Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5
Expected: the reported version is at or above See vendor advisory. Restart the affected service (systemctl restart <service> on Linux, or restart the Windows service) so it loads the patched binary.
Frequently asked questions
Related fixes
Other vulnerabilities in the same area that are worth patching alongside this one:
- How to Fix CVE-2026-38992: n/a (Bundle Sibling) — n/a (Bundle Sibling)
- How to Fix CVE-2026-4063: CWE-862 Missing Authorization — CWE-862 Missing Authorization
- How to Fix CVE-2026-28444: Insecure Direct Object Reference in typebot.io , Insecure Direct Object Reference in typebot.io
- How to Fix CVE-2026-34951: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') , CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- How to Fix CVE-2026-26024: Null pointer dereference in smf , Null pointer dereference in smf
Is CVE-2026-30847 actively exploited?
There is no public confirmation of exploitation in the wild listed in CISA KEV at the time of this writing. Patch anyway. Public exploits commonly follow disclosure within weeks.
Do I need to reboot after patching CVE-2026-30847?
For kernel and OS-level updates, yes. For most userland packages a systemctl restart <service> is enough on Linux, and restarting the Windows service or app on Windows. Any process that loaded the old library keeps using it until restarted.
What is the CVSS score for CVE-2026-30847?
9.3 (Critical). Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:H/SA:H.
Where is the official advisory for CVE-2026-30847?
The vendor advisory is at https://securitylab.github.com/advisories/GHSL-2026-035_Wekan/. The NVD record is at https://nvd.nist.gov/vuln/detail/CVE-2026-30847.
References
- Official vendor advisory: https://securitylab.github.com/advisories/GHSL-2026-035_Wekan/
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-30847
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- Additional reference: https://github.com/wekan/wekan/commit/1c8667eae8b28739e43569b612ffdb2693c6b1ce
- Additional reference: https://github.com/wekan/wekan/releases/tag/v8.34
*Written by Sai Kiran Pandrala. Assembled from the official vendor advisory, NVD record, and CISA KEV listing on 2026-05-25. Always confirm against the vendor's advisory before applying changes in production.*