# CVE-2026-77707: HAVELSAN Liman Render Engine improper certificate validation

Source: https://junglewise.ai/threats/cve-2026-77707-improper-certificate-validation-vulnerability-in-havelsan-inc  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-24. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-77707 · Severity: medium · CVSS 5.9 · Published 2026-09-24

HAVELSAN's Liman Render Engine, a rendering component for visualization applications, contains a flaw in certificate validation that allows an attacker positioned between a client and server to intercept and manipulate encrypted communications. An attacker exploiting this vulnerability could eavesdrop on sensitive data or inject malicious content into the communication stream.

Technologies: [HAVELSAN Liman Render Engine](https://junglewise.ai/threats/technologies/liman-render-engine). Vendors: [HAVELSAN](https://junglewise.ai/threats/vendors/havelsan).

## Quick answers

**Is CVE-2026-77707 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-77707 being exploited in the wild.

**How severe is CVE-2026-77707?** Medium severity, with a CVSS score of 5.9, published 24 September 2026.

**Which products and versions are affected?** HAVELSAN Liman Render Engine 1.0 to before 1.2-75.

**Is there a fix for CVE-2026-77707?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-77707 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-77707?** Check whether you run HAVELSAN Liman Render Engine 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

The Liman Render Engine fails to properly validate SSL/TLS certificates during connection establishment, enabling man-in-the-middle attacks over a network. This allows an adversary on the network path to intercept encrypted communications without detection. The vulnerability affects versions 1.0 through 1.2-75 and requires network positioning but no authentication or user interaction.

## Affected products

- HAVELSAN Liman Render Engine 1.0 to before 1.2-75

## Timeline

- 2026-09-24: disclosed

## References

- [https://siberguvenlik.gov.tr/guvenlik-bildirimleri/detay/tr-26-1172](https://siberguvenlik.gov.tr/guvenlik-bildirimleri/detay/tr-26-1172)

## Related threats

- [HAVELSAN Liman Render Engine privilege escalation via permission assignment](https://junglewise.ai/threats/cve-2026-119474-incorrect-permission-assignment-for-critical-resource)
- [HAVELSAN Liman Render Engine key exchange without entity authentication](https://junglewise.ai/threats/cve-2026-77703-key-exchange-without-entity-authentication-vulnerability-in)