CVE-2023-53680: NFSD: Avoid calling OPDESC() with ops->opnum == OP_ILLEGAL
Vulnerability summary
CVE-2023-53680 is a high (CVSS 7.8) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.30% chance of exploitation in the next 30 days, higher than 23.3% of scored vulnerabilities.
Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 0% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 12 · Related 4Timeline
- 07-10-2025PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
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[].
CVSS metrics
5 scores · 4 sources · 2 versions- CVE.orgCNA7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.30%
Chance of exploitation in the next 30 days
Percentile
23%
Versus all other CVEs
30-day change
Increase +0.01 pp
From 0.30% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu122 products
- linuxAll versions (No fix recorded) | < 5.15.0-79.86
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1042.47
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8, < 50827896c365e0f6c8b55ed56d444dafd87c92c5 | ≥ f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8, < a64160124d5a078be0c380b1e8a0bad2d040d3a1 | ≥ f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8, < ffcbcf087581ae68ddc0a21460f7ecd4315bdd0e | ≥ f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8, < f352c41fa718482979e7e6b71b4da2b718e381cc | ≥ f4f9ef4a1b0a1ca80b152e28e176d69515bdf7e8, < 804d8e0a6e54427268790472781e03bc243f4ee3 | 4.14
- linux_kernel≥ 4.14, < 5.10.220 | ≥ 5.11, < 5.15.107 | ≥ 5.16, < 6.1.24 | ≥ 6.2, < 6.2.11 | 6.3:rc1 | 6.3:rc2 | 6.3:rc3 | 6.3:rc4 | 6.3:rc5
Debian1 product
- linux< 6.1.25-1
3 vendors · 125 products
