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VulnerabilityCVE-2026-80844Published 2026-09-04

CVE-2026-80844 — Linux

Public exploit2 PoC repos

As of 2026-09-04, CVE-2026-80844 is a vulnerability in Linux, EPSS 0.4% (34.9th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-80844, most recently “"LPE Quartet": Public Exploits Released for Four Linux Kernel Local-Root Flaws (DirtyAH6, TUNderflow, PPPoEject, DiagSpill)”.

CVSS
—Not yet scored
EPSS
0.4%Higher than 34.9% of scored CVEs
CISA KEV
NoNot in the KEV catalog
Tracked threats
1Campaigns referencing it
Priority
3.4/10Threadlinqs triage score
Published
EPSS 0.4% (higher than 34.9% of all scored CVEs) · Priority 3.4/10 · Published 2026-09-04

Last updated:

What is CVE-2026-80844?

In the Linux kernel, the following vulnerability has been resolved: xfrm: ah6: validate routing header segments_left AH6 rearranges routing-header addresses before computing or verifying the ICV. ipv6_rearrange_rthdr() assumes that segments_left is not larger than the number of addresses described by the routing header's hdrlen field. That assumption does not hold for raw IPv6 HDRINCL packets. A packet with hdrlen equal to 2 describes one address, but can carry an arbitrary segments_left value. With segments_left equal to 255, the function moves its address pointer 4,064 bytes backwards and passes a 4,064-byte length to memmove(), resulting in an out-of-bounds access. Validate the invariant locally before modifying the routing header or performing any address-pointer arithmetic, and propagate malformed-header errors to the existing AH6 input and output error paths.

1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 31 days ago.

Severity and exploitation probability

EPSS (FIRST)
0.4% probability of exploitation in the next 30 days, higher than 34.9% of all scored CVEs
CISA KEV
Not listed in the CISA Known Exploited Vulnerabilities catalog
Threadlinqs priority
3.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
Published
2026-09-04

Is CVE-2026-80844 being exploited?

Weaponised exploit code for CVE-2026-80844 is publicly available. 2 public proof-of-concept repositories are tracked for this identifier.

Affected products and versions

How to fix CVE-2026-80844

No vendor patch reference has been recorded for CVE-2026-80844 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

Threat activity tracking CVE-2026-80844

1 tracked threat in the Threadlinqs corpus references CVE-2026-80844, either in the campaign’s CVE list or as an indicator on the campaign record.

Sources

Enriched from CVE.org, NVD, FIRST EPSS, public proof-of-concept repositories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.

Other references

Showing 5 of 9 recorded references.