CVE-2026-80809Hinoki check available

Kernel panic via unreserved xattr tree metadata

Published Sep 4, 2026 · Updated Sep 4, 2026

Denial of service in Linux kernel OCFS2 allows local users to panic the kernel by setting a large extended attribute. ocfs2_calc_xattr_set_need() leaves metadata unreserved when an external xattr block already exists, so fragmented allocation fills the value root and a RESTART_META result reaches BUG_ON(). Triggering requires write access to an OCFS2 file, an existing external xattr block, a large xattr value, and filesystem fragmentation; the consequence is a host-wide kernel panic.

CVSS severityUnavailable
Unscored
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Denial of service in Linux kernel OCFS2 allows local users to panic the kernel by setting a large extended attribute. ocfs2_calc_xattr_set_need() leaves metadata unreserved when an external xattr block already exists, so fragmented allocation fills the value root and a RESTART_META result reaches BUG_ON(). Triggering requires write access to an OCFS2 file, an existing external xattr block, a large xattr value, and filesystem fragmentation; the consequence is a host-wide kernel panic.

The record

CVE
CVE-2026-80809
Published
Sep 4, 2026
Updated
Sep 4, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 4, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.6.34.2 <2.6.35
  2. Affected versionversion=2.6.35
  3. Affected versionversion=92f61d8a31e270f9391e7bcc0ac638bd4262a8e0
  4. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <04ba24bce61c917b5b3009f0db470cbb72e26a0d
  5. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <0cdc7dde00ec63ac714271fa8b2918d630b8da1a
  6. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <50f0cbec45b0f3fd7e1263d01916518dbf31eb3f
  7. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <6176313622e34fa3e2b66b9d0682d1e1c6b365c5
  8. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <6a009f1e61b11d9e23d3c5aa1dacfb010945da45
  9. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <743ac908282ac97ef6e73ac3a92df2cc8ecb7479
  10. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <a3ccb57086dd7652d5ecb826486144198a98a8e9
  11. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <b4663405ae29d36011cd712d243456f3f9ab700d
  12. Affected versionversion=a78f9f4668949a6588b8872f162e86685c63d023 <b9eb5c9fdd81d82976d4d5be2b2458eb7d7e46ec

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=2.6.34.2 <2.6.35; version=2.6.35; version=92f61d8a31e270f9391e7bcc0ac638bd4262a8e0; version=a78f9f4668949a6588b8872f162e86685c63d023 <04ba24bce61c917b5b3009f0db470cbb72e26a0d; version=a78f9f4668949a6588b8872f162e86685c63d023 <0cdc7dde00ec63ac714271fa8b2918d630b8da1a; version=a78f9f4668949a6588b8872f162e86685c63d023 <50f0cbec45b0f3fd7e1263d01916518dbf31eb3f; version=a78f9f4668949a6588b8872f162e86685c63d023 <6176313622e34fa3e2b66b9d0682d1e1c6b365c5; version=a78f9f4668949a6588b8872f162e86685c63d023 <6a009f1e61b11d9e23d3c5aa1dacfb010945da45; version=a78f9f4668949a6588b8872f162e86685c63d023 <743ac908282ac97ef6e73ac3a92df2cc8ecb7479; version=a78f9f4668949a6588b8872f162e86685c63d023 <a3ccb57086dd7652d5ecb826486144198a98a8e9; version=a78f9f4668949a6588b8872f162e86685c63d023 <b4663405ae29d36011cd712d243456f3f9ab700d; version=a78f9f4668949a6588b8872f162e86685c63d023 <b9eb5c9fdd81d82976d4d5be2b2458eb7d7e46ec

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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