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TI-2026-79664 Aliases CVE-2026-98907GHSA-2r98-r7qj-j43v

Linux kernel btrfs race in sb_write_pointer() with BLKBSZSET

Priority LOW 22Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Partial Red Hat: 1 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat.

Summary

In the Linux kernel btrfs code, sb_write_pointer() reads the superblock from the block device page cache with read_cache_page_gfp() without serializing against block size changes made through BLKBSZSET. This is the same race that commit 3f29d661e568 fixed for the disk super read. Linux from 6.15 is affected. Red Hat rates it Moderate, and CISA has not added it to KEV.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: btrfs: protect sb_write_pointer() with invalidate lock sb_write_pointer() reads the super block from the block device page cache using read_cache_page_gfp(). This has the same race with BLKBSZSET as the one fixed by commit 3f29d661e568 ("btrfs: sync read disk super and set block size"). Take the mapping invalidate lock around read_cache_page_gfp() to serialize the read against block size changes.

Why it matters now

EPSS 0.00161 5th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.18.53, 7.2Red Hat: 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.15 and later6.18.53, 7.2Patch availableCNA
  • Linux VendorLinux Affected 6.15 and later Fixed in 6.18.53, 7.2 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Install a fixed kernel: 6.18.53 or 7.2, which take the mapping invalidate lock around read_cache_page_gfp(). Red Hat Enterprise Linux 10 has no fix available yet.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA Linux (Linux) Fixed in 6.18.53, 7.2

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Not affected: 6 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenShift Container Platform 5

Timeline

  1. 2026-10-23 Threatist record created from CVE-2026-98907
  2. 2026-10-23 Alias added: GHSA-2r98-r7qj-j43v
  3. 2026-10-26 Fix available: Linux/Linux@0 · CNA
  4. 2026-10-27 Affected versions changed · Red Hat
  5. 2026-10-27 CVSS score added · Red Hat
  6. 2026-11-06 Affected versions changed · Red Hat

References

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21741 →

Sources