# CVE-2026-49206: rapidcsv: Integer overflow in iterator arithmetic causes out-of-bounds access

> Integer overflow in rapidcsv iterator arithmetic allows out-of-bounds access, potentially causing crashes or code execution when processing extremely large CSV files.

- **Severity:** Low 2.9 (`CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Oct 2026
- **Updated:** 15 Oct 2026
- **Also known as:** GHSA-v83v-8j5q-6553

## What is CVE-2026-49206?

CVE-2026-49206 is a low-severity vulnerability in d99kris rapidcsv, published on 14 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

rapidcsv is a C++ CSV parser library. Prior to 8.99, RemoveColumn, InsertColumn, RemoveRow, InsertRow, and GetColumnNames converted size_t indexes to int before adding them to std::vector iterators. On 64-bit systems, in a CSV matrix dimension containing more than 2^31 elements, an index above INT_MAX could wrap to a negative iterator offset and point before the start of the vector, causing undefined behavior, heap memory corruption, or a crash. Triggering the issue requires an extremely large in-memory document, requiring tens of gigabytes of memory at minimum, so typical CSV documents are not practically affected. This issue is fixed in version 8.99.

Weakness: CWE-787 (Out-of-bounds Write), CWE-190 (Integer Overflow or Wraparound)

## Which versions are affected by CVE-2026-49206?


## How do I fix CVE-2026-49206?

No fix has been published for CVE-2026-49206 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-49206 being exploited?

There is no known exploitation of CVE-2026-49206 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49206 and fix it if it is affected.

What it is: CVE-2026-49206 is a low-severity vulnerability in d99kris rapidcsv, published on 14 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-49206 in the wild and no public exploit code.

Affected product: d99kris rapidcsv. 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-2026-49206/ (Markdown: https://insights.sbomify.com/CVE-2026-49206/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49206
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49206
- OSV: https://osv.dev/vulnerability/CVE-2026-49206

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-49206/
Summaries are generated and may contain mistakes; the official description above is the record.