# CVE-2026-125400: Ettercap use-after-free in PCRE filter processing

Source: https://junglewise.ai/threats/cve-2026-125400-ettercap-through-0-8-4-1-contains-a-use-after-free-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-10. Updated: 2026-11-10  
License: CC BY 4.0 with a link back

CVE-2026-125400 · Severity: high · CVSS 8.8 · Published 2026-11-10

Ettercap is a network traffic interception and analysis tool used for security testing and protocol analysis. A use-after-free vulnerability in its packet filtering engine allows attackers on the network to send specially crafted packets that trigger memory corruption and potentially gain root-level code execution on the system running Ettercap.

Technologies: [Ettercap](https://junglewise.ai/threats/technologies/ettercap-ettercap). Vendors: [Ettercap](https://junglewise.ai/threats/vendors/ettercap).

## Quick answers

**Is CVE-2026-125400 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-125400 being exploited in the wild.

**How severe is CVE-2026-125400?** High severity, with a CVSS score of 8.8, published 10 November 2026.

**Which products and versions are affected?** Ettercap through 0.8.4.1.

**Is there a fix for CVE-2026-125400?** 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-2026-125400 attacked?** It is attacked over the network or from the adjacent network, in a software library.

**Am I affected by CVE-2026-125400?** Check whether you run Ettercap 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 use-after-free flaw exists in the func_pcre() function in src/ec_filter.c where the PCRE2 ovector is read after the underlying match data has been freed. Network-adjacent attackers can send packets matching a loaded pcre_regex() substitution filter to exploit this, resulting in memory corruption and potential remote code execution with root privileges. The vulnerability is present through version 0.8.4.1.

## Affected products

- Ettercap Ettercap through 0.8.4.1

## Timeline

- 2026-11-10: disclosed

## References

- [https://github.com/Ettercap/ettercap/blob/v0.8.4.1/src/ec_filter.c](https://github.com/Ettercap/ettercap/blob/v0.8.4.1/src/ec_filter.c)
- [https://github.com/Ettercap/ettercap/commit/1d8badb713579419a29a494bb463a1af59707e98](https://github.com/Ettercap/ettercap/commit/1d8badb713579419a29a494bb463a1af59707e98)

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- [Ettercap heap buffer overflow in Gadu-Gadu dissector](https://junglewise.ai/threats/cve-2026-125401-ettercap-through-0-8-4-1-contains-a-heap-buffer-overflow)