CVE WatchAug 4, 2026

CVE-2023-53669

In the Linux kernel, the following vulnerability has been resolved: tcp: fix skb_copy_ubufs() vs BIG TCP David Ahern reported crashes in s

CVSS

7.8

High

EPSS

0.1%

KEV

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Exploit Today

0-100

Published: Oct 7, 2025 · Last modified: Aug 4, 2026 · CWE-401

EPSS · 30d

0.1%EPSS · 30 days0.1%

2026-08-062026-09-02

Technical description

In the Linux kernel, the following vulnerability has been resolved: tcp: fix skb_copy_ubufs() vs BIG TCP David Ahern reported crashes in skb_copy_ubufs() caused by TCP tx zerocopy using hugepages, and skb length bigger than ~68 KB. skb_copy_ubufs() assumed it could copy all payload using up to MAX_SKB_FRAGS order-0 pages. This assumption broke when BIG TCP was able to put up to 512 KB per skb. We did not hit this bug at Google because we use CONFIG_MAX_SKB_FRAGS=45 and limit gso_max_size to 180000. A solution is to use higher order pages if needed. v2: add missing __GFP_COMP, or we leak memory.

Official references

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