
CVE catalog
CVE-2026-23181
linux: CVE-2026-23181
- Severity
- Medium · CVSS 4.7
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.18% · Oct 25, 2026
In the Linux kernel, the following vulnerability has been resolved: btrfs: sync read disk super and set block size When the user performs a btrfs mount, the block device is not set correctly. The user sets the block size of the block device to 0x4000 by executing the BLKBSZSET command. Since the block size change also changes the mapping->flags value, this further affects the result of the mapping_min_folio_order() calculation. Let's analyze the following two scenarios: Scenario 1: Without executing the BLKBSZSET command, the block size is 0x1000, and mapping_min_folio_order() returns 0; Scenario 2: After executing the BLKBSZSET command, the block size is 0x4000, and mapping_min_folio_order() returns 2. do_read_cache_folio() allocates a folio before the BLKBSZSET command is executed. This results in the allocated folio having an order value of 0. Later, after BLKBSZSET is executed, the block size increases to 0x4000, and the mapping_min_folio_order() calculation result becomes 2. This leads to two undesirable consequences: 1. filemap_add_folio() triggers a VM_BUG_ON_FOLIO(folio_order(folio) < mapping_min_folio_order(mapping)) assertion. 2. The syzbot report [1] shows a null pointer dereference in create_empty_buffers() due to a buffer head allocation failure. Synchronization should be established based on the inode between the BLKBSZSET command and read cache page to prevent inconsistencies in block size or mapping flags before and after folio allocation. [1] KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:create_empty_buffers+0x4d/0x480 fs/buffer.c:1694 Call Trace: folio_create_buffers+0x109/0x150 fs/buffer.c:1802 block_read_full_folio+0x14c/0x850 fs/buffer.c:2403 filemap_read_folio+0xc8/0x2a0 mm/filemap.c:2496 do_read_cache_folio+0x266/0x5c0 mm/filemap.c:4096 do_read_cache_page mm/filemap.c:4162 [inline] read_cache_page_gfp+0x29/0x120 mm/filemap.c:4195 btrfs_read_disk_super+0x192/0x500 fs/btrfs/volumes.c:1367
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | linux | sid | 7.2.12-1 | fixed |
| Debian | linux | forky | 7.2.12-1 | fixed |
| Debian | linux | trixie | 6.12.107-1 | not affected |
| Debian | linux | trixie-security | 6.12.113-1 | not affected |
| Debian | linux | bookworm | 6.1.176-1 | not affected |
| Debian | linux | bookworm-security | 6.1.190-1 | not affected |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | linux | source | sid | 6.18.10-1 | not yet assigned | Not reported | Not reported |
| Debian | linux | source | forky | 6.18.10-1 | not yet assigned | Not reported | Not reported |
| Debian | linux | source | trixie | Not affected | unimportant | Not reported | Not reported |
| Debian | linux | source | bookworm | Not affected | unimportant | Not reported | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [bpftool]Not affected
Source package: [linux]
Details (6)
7.1.0+6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
7.1.0+6.1.176-1· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
7.5.0+6.12.95-1~bpo12+1· amd64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
7.5.0+6.12.95-1~bpo12+1· arm64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
7.1.0+6.1.180-1· amd64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
7.1.0+6.1.180-1· arm64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [hyperv-daemons]Not affected
Source package: [linux]
Details (6)
6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· amd64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· arm64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.1.180-1· amd64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
6.1.180-1· arm64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [intel-sdsi]Not affected
Source package: [linux]
Details (1)
6.12.95-1~bpo12+1· amd64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
- [libcpupower1]Not affected
Source package: [linux]
Details (6)
6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· amd64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· arm64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.1.180-1· amd64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
6.1.180-1· arm64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [libcpupower-dev]Not affected
Source package: [linux]
Details (6)
6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· amd64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· arm64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.1.180-1· amd64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
6.1.180-1· arm64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [linux-bpf-dev]Not affected
Source package: [linux]
Details (2)
6.12.95-1~bpo12+1· amd64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· arm64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
- [linux-compiler-gcc-12-x86]Not affected
Source package: [linux]
Details (2)
6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
6.1.180-1· amd64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [linux-config-6.1]Not affected
Source package: [linux]
Details (4)
6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
6.1.180-1· amd64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
6.1.180-1· arm64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [linux-cpupower]Not affected
Source package: [linux]
Details (6)
6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· amd64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· arm64 · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.1.180-1· amd64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
6.1.180-1· arm64 · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [linux-doc]Not affected
Source package: [linux]
Details (32)
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· all · bookwormNot affected
dsa · linux · debian · bookworm
6.12.43-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.43-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.57-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.57-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.63-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.63-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.69-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.69-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.73-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.73-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.74-2~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.74-2~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.85-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.85-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.86-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.86-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.88-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.88-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.90-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.90-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.90-2~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.90-2~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.94-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.94-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.12.95-1~bpo12+1· all · bookworm-backportsNot affected
dsa · linux · debian · bookworm
6.1.180-1· all · bookworm-securityNot affected
dsa · linux · debian · bookworm
6.1.180-1· all · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [linux-doc-6.1]Not affected
Source package: [linux]
Details (6)
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.176-1· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.180-1· all · bookworm-securityNot affected
dsa · linux · debian · bookworm
6.1.180-1· all · bookworm-securityNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-amd64]Not affected
Source package: [linux]
Details (1)
6.1.170-3· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-arm64]Not affected
Source package: [linux]
Details (1)
6.1.170-3· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-cloud-amd64]Not affected
Source package: [linux]
Details (1)
6.1.170-3· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-cloud-arm64]Not affected
Source package: [linux]
Details (1)
6.1.170-3· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-common]Not affected
Source package: [linux]
Details (2)
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-common-rt]Not affected
Source package: [linux]
Details (2)
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
6.1.170-3· all · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-rt-amd64]Not affected
Source package: [linux]
Details (1)
6.1.170-3· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-47-rt-arm64]Not affected
Source package: [linux]
Details (1)
6.1.170-3· arm64 · bookwormNot affected
dsa · linux · debian · bookworm
- [linux-headers-6.1.0-50-amd64]Not affected
Source package: [linux]
Details (1)
6.1.176-1· amd64 · bookwormNot affected
dsa · linux · debian · bookworm
Observed:
References
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-23181]
- [https://security-tracker.debian.org/tracker/CVE-2026-23181]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23181.json]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-0421.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]