7.5

CVE-2026-68299: linux Improper Input Validation

CVSS: 7.5v3.1HighReceived
AliasesUBUNTU-CVE-2026-68299DEBIAN-CVE-2026-68299
Published 10-08-2026Last modified 19-10-2026
Open JSON

Vulnerability summary

CVE-2026-68299 is a high (CVSS 7.5) Improper Input Validation vulnerability in linux. EPSS estimates a 0.50% chance of exploitation in the next 30 days, higher than 41.9% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.50%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 32 · Related 27
MGASA-2026-0336MGASA-2026-0337OPENSUSE-SU-2026:21910-1RHSA-2026:72624RHSA-2026:74132RHSA-2026:74133

Timeline

  1. 10-08-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: vmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets vmxnet3_get_hdr_len() assumes gdesc->rcd.v4/v6/tcp always describe the outer header, but for a Geneve-encapsulated packet the device can set them based on the inner header instead, signalled by the VMXNET3_RCD_HDR_INNER_SHIFT bit in the completion descriptor. Since the function never skips the outer encapsulation, this mismatch triggers: - BUG_ON(hdr.ipv4->protocol != IPPROTO_TCP), because the outer protocol is UDP (Geneve), not TCP. - BUG_ON(hdr.eth->h_proto != ...), when the tunnel's outer and inner IP versions differ (e.g. outer IPv6/inner IPv4 or vice versa). Check VMXNET3_RCD_HDR_INNER_SHIFT up front and bail out, since the function cannot locate the inner header it would need to parse. Also convert the remaining BUG_ON()s in this function to return 0 defensively.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.50%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

0.00 pp

From 0.50% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.50%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu169 products
  • linuxAll versions (No fix recorded) | < 5.15.0-198.208 | < 6.8.0-147.147 | < 7.0.0-38.38
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124 | < 6.8.0-1067.70 | < 7.0.0-1014.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.187-1 | < 6.12.101-1 | < 7.1.6-1
  • linux-6.12< 6.12.101-1~deb12u1
Linux1 product
  • linux≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < 2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0 | ≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < fbab6b73cc086e32698c86e43d1b16bf17d24c36 | ≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < 28e382646417c7e2be9c9a7079eddf627ff52b90 | ≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < 667b6e52048eaf4dbcf1707ed87ffd44abb9cb38 | ≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < 28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8 | ≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < 4fdb0f162ccdbe9626863b10003855703253fa29 | ≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < b28596baf87e25a078789f1c05817c8a3bf71257 | ≥ 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc, < 34a71f5361fc3adb5b7138da78750b0d535a8252 | 4.2

3 vendors · 172 products

References

27 links
Show all 27 references