# CVE-2026-49836: psd-tools: arbitrary file write via smart-object filename

> Attackers can exploit malicious PSD files to write arbitrary files or read sensitive data via path traversal in psd-tools.

- **Severity:** Medium 4.6 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 10 Sep 2026
- **Updated:** 11 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-49836, GHSA-2rmg-vrx8-9j2f, PYSEC-2026-2969, UBUNTU-CVE-2026-49836

## What is CVE-2026-49836?

CVE-2026-49836 is a medium-severity path traversal vulnerability in psd-tools, published on 10 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

psd-tools is a Python package for working with Adobe Photoshop PSD files. Prior to version 1.17.1, `SmartObject.save()` writes an embedded smart object to a path taken verbatim from the PSD file. Because that name is attacker-controlled and unsanitised, a tool that extracts embedded objects from an untrusted `.psd` can be made to write attacker-chosen bytes to an attacker-chosen path (absolute or `../`-traversing), outside its intended output directory. A secondary issue in `SmartObject.open()` for external-kind smart objects allows the attacker-controlled `fullPath` descriptor to be used as an arbitrary file read path, enabling exfiltration of the read content to the controlled write destination. Both issues are fixed in v1.17.1.

Weakness: CWE-73 (External Control of File Name or Path), CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-49836?

3 open source packages ship an affected version, including psd-tools.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `psd-tools` | PyPI | All versions | 1.17.1 |
| `psd-tools` | PyPI | All versions | 1.17.1 |
| `psd-tools` | PyPI | All versions | 1.17.1 |

## How do I fix CVE-2026-49836?

Upgrade psd-tools to 1.17.1 or later.

## Is CVE-2026-49836 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-49836 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49836 and fix it if it is affected.

What it is: CVE-2026-49836 is a medium-severity path traversal vulnerability in psd-tools, published on 10 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-49836 exists.

Affected packages and fixed versions:
- psd-tools (PyPI): affected all versions; fixed in 1.17.1
- psd-tools (PyPI): affected all versions; fixed in 1.17.1
- psd-tools (PyPI): affected all versions; fixed in 1.17.1

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-2026-49836/ (Markdown: https://insights.sbomify.com/CVE-2026-49836/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49836
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49836
- OSV: https://osv.dev/vulnerability/CVE-2026-49836

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-49836/
Summaries are generated and may contain mistakes; the official description above is the record.