Vulnerability-Lookup

FKIE_CVE-2026-43036

Vulnerability from fkie_nvd - Published: 2026-05-01 15:16 - Updated: 2026-05-08 18:44

Severity ?

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

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

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/cc91202fc20a44aab4c206f12a2bfe05da936051	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d970341cfa5594614c7a6634886c7688b4f5cafd	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ddc748a391dd8642ba6b2e4fe22e7f2ddf84b7f0	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/f7a6cd508e9e825a2c69fa9e13d41ee156852f25	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

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          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
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        "impactScore": 3.6,
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}

CVE-2026-43036 (GCVE-0-2026-43036)

Vulnerability from cvelistv5 – Published: 2026-05-01 14:15 – Updated: 2026-05-11 22:16

Title

net: use skb_header_pointer() for TCPv4 GSO frag_off check

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

4 references

URL	Tags
https://git.kernel.org/stable/c/f7a6cd508e9e825a2…
https://git.kernel.org/stable/c/cc91202fc20a44aab…
https://git.kernel.org/stable/c/d970341cfa5594614…
https://git.kernel.org/stable/c/ddc748a391dd8642b…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: cbc53e08a793b073e79f42ca33f1f3568703540d , < f7a6cd508e9e825a2c69fa9e13d41ee156852f25 (git) Affected: cbc53e08a793b073e79f42ca33f1f3568703540d , < cc91202fc20a44aab4c206f12a2bfe05da936051 (git) Affected: cbc53e08a793b073e79f42ca33f1f3568703540d , < d970341cfa5594614c7a6634886c7688b4f5cafd (git) Affected: cbc53e08a793b073e79f42ca33f1f3568703540d , < ddc748a391dd8642ba6b2e4fe22e7f2ddf84b7f0 (git)
Linux	Linux	Affected: 4.7 Unaffected: 0 , < 4.7 (semver) Unaffected: 6.12.81 , ≤ 6.12.* (semver) Unaffected: 6.18.22 , ≤ 6.18.* (semver) Unaffected: 6.19.12 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-43036

CVE-2026-43036 (GCVE-0-2026-43036)

Tags

Sightings

Nomenclature