Multiple Finka accounting and management software products contain hard-coded Firebird…
Multiple Finka accounting and management software products contain hard-coded Firebird database credentials, allowing local network attackers to read and modify database contents.
CERT Polska coordinated the disclosure of CVE-2025-13776, a vulnerability affecting six Finka software products used for accounting and business management. The vulnerability stems from hard-coded Firebird database credentials that are shared across all instances of the affected software. An attacker positioned on the local network who knows these default credentials can gain unauthorized read and write access to database contents, potentially compromising sensitive financial and business data.
The vulnerability was responsibly disclosed by researcher Wojciech Żebrowski. All affected products have received patches that address the hard-coded credential issue. Organizations using these products should upgrade to the fixed versions immediately to prevent potential data compromise.
Mentioned in this report
Detection guidance
Firebird Database Client Tool Executed with Default SYSDBA Credentials
Detects Firebird database command-line utilities (isql, gbak, qli) invoked with the well-known default SYSDBA/masterkey administrative credentials, which may indicate exploitation of hard-coded Firebird credentials shipped in vulnerable Finka software (CVE-2025-13776). Auto-generated starting point — validate and tune in your environment before deploying. IOC matches can false-positive on shared infrastructure and decay as adversary infrastructure rotates.
title: Firebird Database Client Tool Executed with Default SYSDBA Credentials
id: 9377ad8c-bd4d-5333-aff5-0cd76ccbc523
status: experimental
logsource:
category: process_creation
product: windows
detection:
selection_tool:
Image|endswith:
- \\isql.exe
- \\gbak.exe
- \\qli.exe
selection_creds:
CommandLine|contains:
- SYSDBA
selection_pass:
CommandLine|contains:
- masterkey
condition: selection_tool and selection_creds and selection_pass
fields:
- Image
- CommandLine
- ParentImage
- User
falsepositives:
- Legitimate database administration or backup scripts that still use the vendor default
SYSDBA/masterkey account instead of a changed credential
- Automated backup jobs (gbak) configured by administrators who have not rotated default
Firebird credentials
level: medium
tags:
- attack.t1078
- attack.t1552.001
author: Vorant
Direct Network Connection to Firebird Database Port from Non-Standard Process
Detects TCP connections to the default Firebird database service port (3050) initiated by processes other than the expected Finka application binaries, which may indicate an attacker on the local network leveraging hard-coded default Firebird credentials to access the database directly. Auto-generated starting point — validate and tune in your environment before deploying. IOC matches can false-positive on shared infrastructure and decay as adversary infrastructure rotates.
title: Direct Network Connection to Firebird Database Port from Non-Standard Process
id: 083f38ad-e24b-5581-831e-53deb1ac3d47
status: experimental
logsource:
category: network_connection
product: windows
detection:
selection:
DestinationPort: 3050
Protocol: tcp
filter_app:
Image|endswith:
- \\fbserver.exe
- \\fbguard.exe
- \\firebird.exe
condition: selection and not filter_app
fields:
- Image
- DestinationIp
- DestinationPort
- User
falsepositives:
- Legitimate Finka or other business application clients connecting to the Firebird
server using an unlisted but authorized client binary
- Database administration tools (e.g. IBExpert, FlameRobin) used by IT staff for maintenance
level: low
tags:
- attack.t1078
author: Vorant
Behavioural rules are generated from public reporting — validate in your environment before deploying.
Source reporting: https://cert.pl/en/posts/2026/02/CVE-2025-13776
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