# CVE-2026-48977: OpenSlide: Arbitrary memory write with crafted Ventana BIF file

> OpenSlide library allows arbitrary memory write via crafted Ventana BIF files, potentially leading to code execution or crashes.

- **Severity:** High 7.7 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 18 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-48977, GHSA-mxg2-48g7-fmwc, MGASA-2026-0328, UBUNTU-CVE-2026-48977, openSUSE-SU-2026:11707-1

## What is CVE-2026-48977?

CVE-2026-48977 is a high-severity memory corruption vulnerability in openslide, published on 17 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

OpenSlide is a C library for reading whole slide image files. From 3.4.1 until 4.0.1, OpenSlide's parse_level0_xml() processing in src/openslide-vendor-ventana.c accepts nonpositive row or column tile counts from a crafted Ventana BIF file. The invalid counts produce attacker-controlled relative memory offsets and allow arbitrary values to be written at those offsets, affecting all supported platforms and configurations and resulting in a crash or potential arbitrary code execution. This issue is fixed in version 4.0.1.

Weakness: CWE-823 (Use of Out-of-range Pointer Offset), CWE-1284 (Improper Validation of Specified Quantity in Input), CWE-123 (Write-what-where Condition)

## Which versions are affected by CVE-2026-48977?


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `openslide` | openSUSE:Tumbleweed | All versions | 4.0.1-1.1 |

## How do I fix CVE-2026-48977?

Upgrade to a fixed version.

## Is CVE-2026-48977 being exploited?

There is no known exploitation of CVE-2026-48977 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-48977 and fix it if it is affected.

What it is: CVE-2026-48977 is a high-severity memory corruption vulnerability in openslide, published on 17 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-48977 in the wild and no public exploit code.

Affected product: openslide. 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-2026-48977/ (Markdown: https://insights.sbomify.com/CVE-2026-48977/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48977
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48977
- OSV: https://osv.dev/vulnerability/CVE-2026-48977

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-48977/
Summaries are generated and may contain mistakes; the official description above is the record.