# CVE-2025-40046: linux: In the Linux kernel, the following vulnerability has been resolved:  io_uring/zcrx: fix overshooting recv limit  It's...

CVE-2025-40046 is fixed in linux on 1 platform by DEBIAN-CVE-2025-40046 (version 6.17.6-1), released October 28, 2025. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2025-40046
- Priority: High
- CVSS: 8.6 (high)
- EPSS: 0.0035
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 28, 2025

## Description

In the Linux kernel, the following vulnerability has been resolved:  io_uring/zcrx: fix overshooting recv limit  It's reported that sometimes a zcrx request can receive more than was requested. It's caused by io_zcrx_recv_skb() adjusting desc->count for all received buffers including frag lists, but then doing recursive calls to process frag list skbs, which leads to desc->count double accounting and underflow.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 14 | 6.17.6-1 | [DEBIAN-CVE-2025-40046](https://patchblox.com/security/data/fix/linux/debian-cve-2025-40046.md) | Oct 28, 2025 |

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Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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