---
title: "CVE-2026-55211: surfio has an out-of-bounds read"
url: https://erroneo.us/security/cve/CVE-2026-55211/
description: "CVE-2026-55211 (surfio (PyPI)): Surfio is a library for reading and writing surface files. Prior to 0.0.19, surfio does not correctly validate size fields…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-09-15
date_modified: 2026-09-17
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-55211"
kev: false
cvss: 9.8
epss: 0.00744
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-55211: surfio has an out-of-bounds read

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.7% , percentile 54: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 54% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes surfio (PyPI) < 0.0.19, fixed in 0.0.19 . Check your lockfile, including transitive dependencies.

## What it is

Surfio is a library for reading and writing surface files. Prior to 0.0.19, surfio does not correctly validate size fields in IRAP files, leading to a buffer overflow when untrusted files are parsed. The severity assumes surfio is used to parse untrusted files in a networking context such as a web service. This issue is fixed in version 0.0.19.

## Affected packages

- PyPI `surfio` < 0.0.19 → fixed: 0.0.19

## Affected products (CVE record)

- equinor surfio: < 0.0.19

## Severity

- GitHub_M CVSS 3.0: 9.8 `CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.74% probability of exploitation activity in the next 30 days; percentile 54.

## Sources

- [GitHub Advisory GHSA-rcr2-hggw-43wm](https://github.com/advisories/GHSA-rcr2-hggw-43wm)
- [CVE.org record CVE-2026-55211](https://www.cve.org/CVERecord?id=CVE-2026-55211)
- [NVD entry CVE-2026-55211](https://nvd.nist.gov/vuln/detail/CVE-2026-55211)
- [github.com](https://github.com/equinor/surfio/security/advisories/GHSA-rcr2-hggw-43wm)
- [github.com](https://github.com/equinor/surfio/pull/86)
- [github.com](https://github.com/equinor/surfio/commit/1619750bce28e39c4f378d2fb6d28b72380a12aa)
- [github.com](https://github.com/equinor/surfio/commit/e009c0cad145484f854aeb22d1979f9216b291db)
- [github.com](https://github.com/equinor/surfio/releases/tag/0.0.19)

---
Source page: https://erroneo.us/security/cve/CVE-2026-55211/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt