# CVE-2026-35095: KTM System e-BOK session fixation

Source: https://junglewise.ai/threats/cve-2026-35095-ktm-system-e-bok-session-fixation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-30. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-35095 · Severity: info · CVSS 4.8 · Published 2026-06-30

KTM System e-BOK is a web portal used by housing cooperatives to allow residents to view personal data, billing information, and payment history. A security flaw allows an attacker to fix a user's session ID before they log in, which can lead to the attacker hijacking the user's account once they authenticate. This could result in unauthorized access to a resident's financial records, personal details, and account settings.

Technologies: [KTM System e-BOK](https://junglewise.ai/threats/technologies/e-bok). Vendors: [KTM System](https://junglewise.ai/threats/vendors/ktm-system).

## Quick answers

**Is CVE-2026-35095 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-35095 being exploited in the wild.

**How severe is CVE-2026-35095?** Informational severity, with a CVSS score of 4.8, published 30 June 2026.

**Which products and versions are affected?** KTM System e-BOK All versions prior to June 2026 update.

**Is there a fix for CVE-2026-35095?** A patch was published on 2026-06-01: Patch released in June 2026 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-35095 attacked?** It is attacked with local access, in a web application.

**Am I affected by CVE-2026-35095?** Check whether you run KTM System e-BOK at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A session fixation vulnerability (CWE-384) exists in KTM System e-BOK because the application allows the client to set a session identifier prior to authentication. If a cookie with a valid name is provided by the client, the application fails to regenerate the session ID upon a successful login, maintaining the pre-authentication value. An attacker can exploit this by forcing a specific session ID on a victim's browser (e.g., via physical access or local network manipulation) and then hijacking the session once the victim logs in. The issue was addressed in the June 2026 patch.

## Affected products

- KTM System e-BOK All versions prior to June 2026 update

## Timeline

- 2026-06-30: advisory: Advisory published by CERT.PL
- 2026-06-30: disclosed
- 2026-06-01: patched: Patch released in June 2026

## References

- [https://cert.pl/posts/2026/06/CVE-2026-35095/](https://cert.pl/posts/2026/06/CVE-2026-35095/)
- [https://ktmsystem.pl/internetowe-biuro-obslugi-klienta/](https://ktmsystem.pl/internetowe-biuro-obslugi-klienta/)

## Related threats

- [KTM System e-BOK improper rate limiting in login](https://junglewise.ai/threats/cve-2026-35098-ktm-system-e-bok-improper-rate-limiting-in-login)
- [KTM System e-BOK weak password requirements](https://junglewise.ai/threats/cve-2026-35097-ktm-system-e-bok-weak-password-requirements)
- [KTM System e-BOK CSRF in email and password change functions](https://junglewise.ai/threats/cve-2026-35096-ktm-system-e-bok-csrf-in-email-and-password-change-functions)