9.1

CVE-2023-38431: linux linux_kernel Out-of-bounds Read

Modified
AliasesUBUNTU-CVE-2023-38431DEBIAN-CVE-2023-38431
Published 17-07-2023Last modified 02-08-2024

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.

Priority
Prioritisesevere

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?
CVSS score
9.1/10
010
Critical · v3.1 (NVD)
EPSS score
1.16%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 4 · Related 4

Timeline

  1. 17-07-2023
    PublishedVulnerability first disclosed.
  2. 02-08-2024
    Last 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

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

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

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
Show all 12 references