CVE-2023-38431: linux linux_kernel Out-of-bounds Read
Vulnerability summary
CVE-2023-38431 is a critical (CVSS 9.1) Out-of-bounds Read vulnerability in linux linux_kernel. EPSS estimates a 1.16% chance of exploitation in the next 30 days, higher than 67% of scored vulnerabilities.
Severe, CVSS 9.1 (NVD); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 4 · Related 4Timeline
- 17-07-2023PublishedVulnerability first disclosed.
- 02-08-2024Last modifiedVulnerability information updated.
Description
An issue was discovered in the Linux kernel before 6.3.8. fs/smb/server/connection.c in ksmbd does not validate the relationship between the NetBIOS header's length field and the SMB header sizes, via pdu_size in ksmbd_conn_handler_loop, leading to an out-of-bounds read.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- OSV · DebianEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS trend
Probability
1.16%
Chance of exploitation in the next 30 days
Percentile
67%
Versus all other CVEs
30-day change
No change 0.00 pp
From 1.16% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not 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.
Ubuntu92 products
- linux< 5.15.0-102.112
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 5.15.0-1057.63
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Netapp5 products
Debian1 product
- linux< 6.1.37-1 | < 6.3.11-1
Linux1 product
- linux_kernel≥ 5.15, < 5.15.145 | ≥ 5.16, < 6.1.34 | ≥ 6.2, < 6.3.8
4 vendors · 99 products
References
12 links- security.netapp.com/advisory/ntap-20230824-0011/Third Party Advisory