9.8

CVE-2026-31608: smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()

Analyzed
AliasesUBUNTU-CVE-2026-31608DEBIAN-CVE-2026-31608CGA-2vrv-gqq2-9mc9
Published 24-04-2026Last modified 05-08-2026

Vulnerability summary

CVE-2026-31608 is a critical (CVSS 9.8) Double Free vulnerability in linux. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 39.6% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 9.8 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 0% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.46%
0%100%
Low · -0.21 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 6 · Related 7

Timeline

  1. 24-04-2026
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list() smb_direct_flush_send_list() already calls smb_direct_free_sendmsg(), so we should not call it again after post_sendmsg() moved it to the batch list.

CVSS metrics

6 scores · 5 sources · 2 versions

EPSS trend

Probability

0.46%

Chance of exploitation in the next 30 days

Percentile

40%

Versus all other CVEs

30-day change

Decrease -0.21 pp

From 0.67% 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.

Ubuntu98 products
  • linux< 7.0.0-27.27
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 7.0.0-1008.8
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Chainguard11 products
  • linux-aws-6.12All versions (No fix recorded)
  • linux-aws-6.18< 6.18.31-r0
  • linux-azure-6.12All versions (No fix recorded)
  • linux-azure-6.18< 6.18.31-r0
  • linux-gcp-6.12All versions (No fix recorded)
Linux2 products
  • linux≥ 5ef18a2e66f2f33fdac64437bddfb9fe6389fdc7, < 6968c91fab05b8fc4d6700e0cf34472bb422df25 | ≥ 79242e7b6bc63efec28b7c235bc320806afce6c0, < 2ba03f46132b0d1a7bafb86e1ef61951a2254023 | ≥ 34abd408c8ba24d7c97bd02ba874d8c714f49db1, < 830de6eeb9db4cb7e758201fb99328ef4ca4b032 | ≥ 34abd408c8ba24d7c97bd02ba874d8c714f49db1, < 84ff995ae826aa6bbcc6c7b9ea569ff67c021d72 | ≥ 6.18.11, < 6.18.24 | ≥ 6.19.1, < 6.19.14 | 7.0
  • linux_kernel< 6.18.24 | ≥ 6.19, < 6.19.14 | ≥ 7.0, < 7.0.1
Debian1 product
  • linux< 6.19.14-1

4 vendors · 112 products

References

16 links
Show all 16 references