CVE-2023-53669

low-risk
Published 2025-10-07

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.

Do I need to act?

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0.01% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
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Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.5/10 Medium
LOCAL / LOW complexity

Affected Products (1)

Affected Vendors

Linux

References (4)

Patch https://git.kernel.org/stable/c/3c77a377877acbaf03cd7caa21d3644a5dd16301
Patch https://git.kernel.org/stable/c/7e692df3933628d974acb9f5b334d2b3e885e2a6
Patch https://git.kernel.org/stable/c/7fa93e39fbb0566019c388a8038a4d58552e0910
Patch https://git.kernel.org/stable/c/9cd62f0ba465cf647c7d8c2ca7b0d99ea0c1328f
23
/ 100
low-risk
Severity 18/34 · Moderate
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal