5.5

CVE-2026-31738: vxlan: validate ND option lengths in vxlan_na_create

Analyzed
AliasesUBUNTU-CVE-2026-31738DEBIAN-CVE-2026-31738
Published 01-05-2026Last modified 23-05-2026

Vulnerability summary

CVE-2026-31738 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 2% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.12%
0%100%
Low · -0.04 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 119 · Related 117
MGASA-2026-0108MGASA-2026-0110SUSE-SU-2026:21834-1SUSE-SU-2026:2195-1SUSE-SU-2026:2238-1SUSE-SU-2026:22964-1

Showing 100 of 119.

Timeline

  1. 01-05-2026
    PublishedVulnerability first disclosed.
  2. 23-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: vxlan: validate ND option lengths in vxlan_na_create vxlan_na_create() walks ND options according to option-provided lengths. A malformed option can make the parser advance beyond the computed option span or use a too-short source LLADDR option payload. Validate option lengths against the remaining NS option area before advancing, and only read source LLADDR when the option is large enough for an Ethernet address.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.12%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

Decrease -0.04 pp

From 0.16% 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

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu157 products
  • linuxAll versions (No fix recorded) | < 5.15.0-186.196 | < 6.8.0-136.136
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1112.119 | < 6.8.0-1061.64
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < 901c1dd3bab2955d7e664f914c374c8c3ac2b958 | ≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < e476745917a1e288eb15e7ff49d286a86a4861d3 | ≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < 2029712fb2c87e9a8c75094906f2ee29bf08c500 | ≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < 602596c69a70e50d9ab8c6ae0290a01f88229dd7 | ≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < de20d2e3b9179d132f5f5b44e490d7c916c6321b | ≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < eddfce70a6f3107d1679b0c2fcbeb96b593bd679 | ≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < b69c4236255bd8de16cd876e58c6f0867d1d78b1 | ≥ 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa, < afa9a05e6c4971bd5586f1b304e14d61fb3d9385 | d8be18c52dbc94989f6d74637b731af39cd3d902 | 3927dace523706cc00f808520eaf2125dd7c07b5 | ≥ 3.12.18, < 3.13 | ≥ 3.13.10, < 3.14 | 3.14
  • linux_kernel≥ 3.12.18, < 3.13 | ≥ 3.13.10, < 3.14 | ≥ 3.14.1, < 5.10.253 | ≥ 5.11, < 5.15.203 | ≥ 5.16, < 6.1.168 | ≥ 6.2, < 6.6.134 | ≥ 6.7, < 6.12.81 | ≥ 6.13, < 6.18.22 | ≥ 6.19, < 6.19.12 | 3.14 | 3.14:rc8 | 7.0:rc1 | 7.0:rc2 | 7.0:rc3 | 7.0:rc4 | 7.0:rc5 | 7.0:rc6
Debian1 product
  • linux< 6.1.170-1 | < 6.12.85-1 | < 6.19.12-1

3 vendors · 160 products

References

39 links
Show all 39 references