CVE-2023-53680 NFSD: Avoid calling OPDESC() with ops->opnum == OP_ILLEGAL

What is CVE-2023-53680?

CVE-2023-53680 is a high-severity memory corruption vulnerability in Linux kernel, published on 7 Oct 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

NFSD: Avoid calling OPDESC() with ops->opnum == OP_ILLEGAL

OPDESC() simply indexes into nfsd4_ops[] by the op's operation number, without range checking that value. It assumes callers are careful to avoid calling it with an out-of-bounds opnum value.

nfsd4_decode_compound() is not so careful, and can invoke OPDESC() with opnum set to OP_ILLEGAL, which is 10044 -- well beyond the end of nfsd4_ops[].

Weakness: CWE-787

Which versions are affected by CVE-2023-53680?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2023-53680?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2023-53680 being exploited?

There is no known exploitation of CVE-2023-53680 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2023-53680, DEBIAN-CVE-2023-53680, GHSA-6qhx-j6v2-cx4m, UBUNTU-CVE-2023-53680.