Vulnerability · CVE-2026-43036
In the Linux kernel, the following vulnerability has been resolved: net: use skb_header_pointer() for TCPv4 GSO frag_off check Syzbot reported a KMSAN uninit-value war…
Published May 1, 2026 · catalog updated Jun 17, 2026 · linux kernel
Check if you run it
No confirmed exploitation is on record for CVE-2026-43036. EPSS is 0.12%. Act only if a listed version of linux kernel is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium5.5
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.12%
- Remediation
- Advisory link
- Affected products
- cpe linux/linux kernel
In the Linux kernel, the following vulnerability has been resolved: net: use skb_header_pointer() for TCPv4 GSO frag_off check Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1]. gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header offsets that are not always safe for direct dereference on packets injected from PF_PACKET paths. Use skb_header_pointer() for the TCPv4 frag_off check so the header read is robust whether data is already linear or needs copying. [1] https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe linux/linux kernel7.0
How to fix CVE-2026-43036
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-43036. EPSS is 0.12%. Act only if a listed version of linux kernel is installed.
Which versions are affected?
Compare what you have installed with linux/linux kernel 7.0. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-908: Use of Uninitialized Resource. EPSS 0.12%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
May 1, 2026 · NIST NVD
Detected
In the Linux kernel, the following vulnerability has been resolved: net: use skb_header_pointer() for TCPv4 GSO frag_off check Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1]. gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header of
Jun 17, 2026 · NIST NVD
Updated
In the Linux kernel, the following vulnerability has been resolved: net: use skb_header_pointer() for TCPv4 GSO frag_off check Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1]. gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header of
Sources
- CVE.orgVulnerability recordCVE-2026-43036
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-43036
30-day exploitation probability 0.1%
first.org - NIST NVDVulnerability recordCVE-2026-43036
In the Linux kernel, the following vulnerability has been resolved: net: use skb_header_pointer() for TCPv4 GSO frag_off check Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1]. gso_features_check() reads iph->frag_off to
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.