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Vulnerability Database

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A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

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A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

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Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

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361,925

Total vulnerabilities in the database

CVE-2026-52819 — kimai / kimai

Incorrect Authorization

Summary

GET /api/timesheets?user=<id> (and users[]=<id>) returns the targeted user's timesheet records to any caller that has the view_other_timesheet permission, without verifying that the caller is teamlead of any team containing the target user. The per-record endpoint GET /api/timesheets/{id} correctly enforces this check via TimesheetVoter/RolePermissionManager::checkTeamAccessTimesheet → checkTeamLeadAccess, but the list endpoint only filters projects/customers by team membership and never validates t.user. A ROLE_TEAMLEAD user can therefore enumerate any user's records — including the rate field — as long as those records are on a project with no team scoping (Kimai's default) or on any project that shares any team (membership, not lead) with the requester.

Details

Root cause: authorization mismatch between the per-record voter and the list endpoint.

Per-record path (correct)

src/Voter/TimesheetVoter.php:138:

if (!$this-&gt;permissionManager-&gt;checkTeamAccessTimesheet($subject, $user)) {
    return false;
}
return $this-&gt;permissionManager-&gt;hasRolePermission($user, $permission . &#039;_other_timesheet&#039;);

checkTeamLeadAccess (RolePermissionManager.php:143-160) requires isTeamleadOf (not just member) one of the target user's teams. The unit test testTeamleadDeniedWhenOnlyPlainMemberOfOwnerTeam (tests/Voter/TimesheetVoterTest.php:253-269) codifies this:

> "a TEAMLEAD role with view_other_timesheet must not access another user's timesheet by being a plain team member — they must be the team's teamlead."

List path (vulnerable)

src/API/TimesheetController.php:97-119:

public function cgetAction(ParamFetcherInterface $paramFetcher, ..., UserRepository $userRepository): Response
{
    $query = new TimesheetQuery(false);
    $this-&gt;prepareQuery($query, $paramFetcher);
    $seeAll = false;

    if ($this-&gt;isGranted(&#039;view_other_timesheet&#039;)) {
        /** @var array&lt;int&gt; $users */
        $users = $paramFetcher-&gt;get(&#039;users&#039;);
        $userId = $paramFetcher-&gt;get(&#039;user&#039;);

        if (&#039;all&#039; === $userId) {
            $seeAll = true;
        } elseif (\is_string($userId) &amp;&amp; $userId !== &#039;&#039;) {
            $users[] = (int) $userId;
        }

        if (!$seeAll) {
            foreach ($userRepository-&gt;findByIds($users) as $user) {
                $query-&gt;addUser($user);   // &lt;-- no teamlead-of-target check
            }
        }
    }
    ...

config/packages/kimai.yaml:96,115 grants TIMESHEET_OTHER (which contains view_other_timesheet) to ROLE_TEAMLEAD, so the gate at line 103 passes for any teamlead. The user= / users[]= IDs are pushed straight into the query.

Net effect

For any victim bob who:

has at least one team that the requester alice is not teamlead of (so the voter denies per-record access), AND
has timesheets either on a project with no team (Kimai's default), or on a project that shares any team with alice (membership, not lead)

alice is denied via GET /api/timesheets/{id} but receives bob's records via GET /api/timesheets?user=<bob_id>.

Disclosed fields in the collection response include description, begin, end, duration, billable, exported, tags, rate, internalRate, plus project/activity/user IDs (Default/Collection serializer groups, Timesheet.php:164-173). rate is financial data that the per-record voter is supposed to gate via the separate view_rate_other_timesheet permission.

Why other proposed mitigations don't apply

The view_other_timesheet IsGranted on the route is the only authorization layer in the list path; ROLE_TEAMLEAD has it globally.
prepareQuery only sets currentUser, not authorization (BaseApiController.php:68-71).
The serializer does not filter rate per caller — it is a static Default-group property.
Recent commit 20c7b03 "Re-usable ACL checks on teams" hardened the voter side but left the list endpoint unchanged.

A PoC was provided, but removed for security reasons.

Impact

Authorization bypass: a ROLE_TEAMLEAD (a non-admin role typically granted to multiple users in a Kimai instance) can read any other user's timesheet records
Financial data disclosure: the rate and internalRate fields are returned in the collection serializer group, leaking what gets billed/costed against any user's records.
PII / activity disclosure: per-entry description, begin, end, duration, billable, exported, project/activity/customer IDs, and tags are leaked, allowing reconstruction of any user's activity timeline.

Solution

The list of requested user TimesheetController::cgetAction() is now guarded with the access_user permission. The access_user permission verifies that the requesting user is allowed to see each of the requested user. If any of the requested users may not be seen, the entire call will fail.

Find out more at https://www.kimai.org/en/security/ghsa-4m8q-55qv-9pwp

Published: Jul 13, 2026
Updated: Jul 14, 2026
CVE: CVE-2026-52819
GHSA: GHSA-4m8q-55qv-9pwp
Severity: Medium
Exploit:
CISA KEV:

No technical information available.

CWEs:

CWE-863

Affected Software
References

Software	From	Fixed in
kimai / kimai	-	2.57.0

https://github.com/kimai/kimai/security/advisories/GHSA-4m8q-55qv-9pwp

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Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.