# CVE-2023-4256: tcpreplay: Within tcpreplay's tcprewrite, a double free vulnerability has been identified in the tcpedit_dlt_cleanup() function...

CVE-2023-4256 is fixed in tcpreplay on 1 platform, first by DEBIAN-CVE-2023-4256, released December 21, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-4256
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0033
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 21, 2023

## Description

Within tcpreplay's tcprewrite, a double free vulnerability has been identified in the tcpedit_dlt_cleanup() function within plugins/dlt_plugins.c. This vulnerability can be exploited by supplying a specifically crafted file to the tcprewrite binary. This flaw enables a local attacker to initiate a Denial of Service (DoS) attack.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | tcpreplay Debian 13.5 (trixie) | 4.5.1-1 | [DEBIAN-CVE-2023-4256](https://patchblox.com/security/data/fix/linux/debian-cve-2023-4256.md) | Dec 21, 2023 |
| Linux | tcpreplay Debian 14 | 4.5.1-1 | [DEBIAN-CVE-2023-4256](https://patchblox.com/security/data/fix/linux/debian-cve-2023-4256.md) | Dec 21, 2023 |
| Linux | tcpreplay Ubuntu 18.04.6 LTS (bionic) | 4.2.6-1ubuntu0.1~esm5 | [tcpreplay 4.2.6-1ubuntu0.1~esm5](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-tcpreplay-4.2.6-1ubuntu0.1-esm5.md) | Mar 12, 2024 |
| Linux | tcpreplay Ubuntu 20.04 LTS (focal) | 4.3.2-1ubuntu0.1~esm3 | [tcpreplay 4.3.2-1ubuntu0.1~esm3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-tcpreplay-4.3.2-1ubuntu0.1-esm3.md) | Mar 12, 2024 |
| Linux | tcpreplay Ubuntu 22.04.1 LTS (jammy) | 4.3.4-1ubuntu0.1~esm2 | [tcpreplay 4.3.4-1ubuntu0.1~esm2](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-tcpreplay-4.3.4-1ubuntu0.1-esm2.md) | Mar 12, 2024 |
| Linux | tcpreplay Ubuntu 24.04.5 LTS (noble) | 4.4.4-1ubuntu0.1~esm1 | [tcpreplay 4.4.4-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-tcpreplay-4.4.4-1ubuntu0.1-esm1.md) | Mar 12, 2024 |
| Linux | tcpreplay opensuse-leap 16.0 | 4.5.2-bp160.1.1 | [OPENSUSE-SU-2025:20119-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20119-1.md) | Nov 27, 2025 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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