# CVE-2026-45761: Suricata heap buffer overflow in rule parsing

Source: https://junglewise.ai/threats/cve-2026-45761-suricata-heap-buffer-overflow-in-rule-parsing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-10. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-45761 · Severity: low · CVSS 3.3 · Published 2026-09-10

Suricata is a network security monitoring and intrusion detection/prevention system used to analyze traffic for threats. A maliciously crafted detection rule with mixed-case frame syntax can trigger a heap buffer overflow when Suricata loads signatures, potentially causing the service to crash and disrupting threat monitoring capabilities. This requires an attacker to provide or modify the ruleset being loaded.

Technologies: [OISF Suricata](https://junglewise.ai/threats/technologies/suricata). Vendors: [OISF](https://junglewise.ai/threats/vendors/oisf).

## Quick answers

**Is CVE-2026-45761 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-45761 being exploited in the wild.

**How severe is CVE-2026-45761?** Low severity, with a CVSS score of 3.3, published 10 September 2026.

**Which products and versions are affected?** OISF Suricata before 7.0.16 and 8.0.5.

**Is there a fix for CVE-2026-45761?** A patch was published on 2026-05-19. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-45761 attacked?** It is attacked with local access, in a hosted service.

**Am I affected by CVE-2026-45761?** Check whether you run OISF Suricata 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 heap-based buffer overflow (CWE-122) occurs in Suricata's rule parsing logic when processing frame syntax with mixed case. The vulnerability is triggered during rule loading/parsing, not by network traffic, and requires the attacker to control or influence the ruleset being loaded by Suricata. The flaw allows limited impact to availability (service DoS) with low privilege and local attack requirements. Patches are available in versions 7.0.16 and 8.0.5; workarounds include preprocessing rules to enforce lowercase frame syntax and only loading trusted rulesets.

## Affected products

- OISF Suricata before 7.0.16 and 8.0.5

## Timeline

- 2026-06-02: disclosed
- 2026-05-19: patched

## References

- [https://forum.suricata.io/t/suricata-8-0-5-and-7-0-16-released/6315](https://forum.suricata.io/t/suricata-8-0-5-and-7-0-16-released/6315)
- [https://github.com/OISF/suricata/security/advisories/GHSA-r74x-74x5-r9vm](https://github.com/OISF/suricata/security/advisories/GHSA-r74x-74x5-r9vm)

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