How severe is CVE-2026-53091?

CVE-2026-53091 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.

Is CVE-2026-53091 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-53091?

CVE-2026-53091 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-53091?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-53091 have an EU (EUVD) identifier?

Yes. CVE-2026-53091 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38959.

When was CVE-2026-53091 published?

CVE-2026-53091 was published on 2026-06-24 and last updated on 2026-07-23.

CVE-2026-53091

CVE-2026-53091 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 8.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-131.

Key facts

Severity: High (CVSS 3.x base score 8.4)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-38959
Weakness: CWE-131
Affected product: Linux Linux Kernel
Published: 2026-06-24
Last modified: 2026-07-23

Description

In the Linux kernel, the following vulnerability has been resolved: net: pull headers in qdisc_pkt_len_segs_init() Most ndo_start_xmit() methods expects headers of gso packets to be already in skb->head. net/core/tso.c users are particularly at risk, because tso_build_hdr() does a memcpy(hdr, skb->data, hdr_len); qdisc_pkt_len_segs_init() already does a dissection of gso packets. Use pskb_may_pull() instead of skb_header_pointer() to make sure drivers do not have to reimplement this. Some malicious packets could be fed, detect them so that we can drop them sooner with a new SKB_DROP_REASON_SKB_BAD_GSO drop_reason.

Frequently asked questions

What is CVE-2026-53091?: In the Linux kernel, the following vulnerability has been resolved: net: pull headers in qdisc_pkt_len_segs_init() Most ndo_start_xmit() methods expects headers of gso packets to be already in skb->head. net/core/tso.c users are particularly at risk, because tso_build_hdr() does a memcpy(hdr, skb->data, hdr_len); qdisc_pkt_len_segs_init() already does a dissection of gso packets. Use pskb_may_pull() instead of skb_header_pointer() to make sure drivers do not have to reimplement this. Some malicious packets could be fed, detect them so that we can drop them sooner with a new SKB_DROP_REASON_SKB_BAD_GSO drop_reason.
How severe is CVE-2026-53091?: CVE-2026-53091 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability high.
Is CVE-2026-53091 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-53091?: CVE-2026-53091 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-53091?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-53091 have an EU (EUVD) identifier?: Yes. CVE-2026-53091 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38959.
When was CVE-2026-53091 published?: CVE-2026-53091 was published on 2026-06-24 and last updated on 2026-07-23.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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