---
id: "CVE-2026-122136"
kind: "vulnerability"
aliases: ["CVE-2026-122136"]
title: "Powerlevel10k: predictable temp file lets local users overwrite victim files"
severity: "medium"
cvss: 4.4
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["multi-user", "package", "powerlevel10k", "shell", "zsh"]
not_affected_if: ["private-tmpdir", "single-user-machine", "version-1.20.19-or-later"]
published_at: "2026-11-04T21:18:09+00:00"
first_seen_at: "2026-11-04T21:49:20+00:00"
updated_at: "2026-11-04T21:51:30+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-122136", "first_seen_at": "2026-11-04T21:49:20+00:00"}]
exploit_sources: []
---

# Powerlevel10k: predictable temp file lets local users overwrite victim files

Powerlevel10k, a Zsh prompt theme, writes its instant-prompt cache to a predictable path in TMPDIR and follows symlinks there. A local attacker who pre-plants a symlink can make shell startup truncate and overwrite files the victim can write.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version with `p10k version` or the theme's git tag where it was cloned.
- Look for `p10k-instant-prompt-` files in TMPDIR that are symlinks, using `ls -l $TMPDIR`.

## Fix

- Powerlevel10k `1.20.19` (fixed version per the advisory; affected: before `1.20.19`).

## Timeline

- 2026-11-04T21:49:20+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-122136

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/powerlevel10k-before-1.20.19-symlink-following-via-instant-prompt-temporary-file
- [fix] Patch: github.com https://github.com/romkatv/powerlevel10k/commit/7ddd1b2715c3844275214347a3572ac1fdd6dc39

## From the sources

Powerlevel10k before 1.20.19 contains a symlink following vulnerability in _p9k_dump_instant_prompt that allows local attackers to overwrite victim-writable files via a predictable temporary path. Attackers can pre-plant symlinks at p10k-instant-prompt-output-<user>-<pid> in TMPDIR, guessing the victim's shell PID, so shell startup truncates and overwrites targeted files.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_