# CVE-2026-13590: seladb PcapPlusPlus Modbus Protocol ModbusLayer.h getLength heap-based overflow

> A heap-based buffer overflow in PcapPlusPlus Modbus handler allows remote attackers to potentially execute code or cause denial of service.

- **Severity:** Medium 6.3 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 29 Jun 2026
- **Updated:** 30 Jun 2026
- **Also known as:** GHSA-r3g9-96ff-r4rp

## What is CVE-2026-13590?

CVE-2026-13590 is a medium-severity memory corruption vulnerability in seladb PcapPlusPlus, published on 29 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A security flaw has been discovered in seladb PcapPlusPlus 25.05. This impacts the function pcpp::ModbusLayer::getLength in the library Packet++/header/ModbusLayer.h of the component Modbus Protocol Handler. The manipulation of the argument length results in heap-based buffer overflow. The attack can be launched remotely. A high complexity level is associated with this attack. The exploitability is said to be difficult. The exploit has been released to the public and may be used for attacks. The patch is identified as 4c90c3e3418a2b09dc82b7ca5775e9c1e22fe454. Applying a patch is advised to resolve this issue.

Weakness: CWE-122 (Heap-based Buffer Overflow), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2026-13590?


## How do I fix CVE-2026-13590?

Apply the vendor's patch.

## Is CVE-2026-13590 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-13590 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-13590 and fix it if it is affected.

What it is: CVE-2026-13590 is a medium-severity memory corruption vulnerability in seladb PcapPlusPlus, published on 29 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-13590 exists.

Affected product: seladb PcapPlusPlus. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-13590/ (Markdown: https://insights.sbomify.com/CVE-2026-13590/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-13590
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-13590
- OSV: https://osv.dev/vulnerability/CVE-2026-13590

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-13590/
Summaries are generated and may contain mistakes; the official description above is the record.