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CVE Record

CVE-2026-80631: btrfs: lzo: reject compressed segment that overflows the compressed input

In the Linux kernel, the following vulnerability has been resolved: btrfs: lzo: reject compressed segment that overflows the compressed input lzo_decompress_bio() validates each on-disk segment length seg_len only against the workspace cbuf size, not against the compressed input size (compressed_len, the total folio bytes of the bio). A crafted extent can carry a segment whose seg_len passes the cbuf check but runs past the end of the bio, so copy_compressed_segment() walks off the last folio: get_current_folio() then returns the NULL folio from bio_next_folio(), and with CONFIG_BTRFS_ASSERT disabled (default) folio_size(NULL) faults. BUG: KASAN: null-ptr-deref in lzo_decompress_bio (fs/btrfs/lzo.c:383) Read of size 8 at addr 0000000000000000 by task kworker/u8:1/29 Workqueue: btrfs-endio simple_end_io_work kasan_report (mm/kasan/report.c:590) lzo_decompress_bio (fs/btrfs/lzo.c:383) end_bbio_compressed_read (fs/btrfs/compression.c:1065) btrfs_bio_end_io (fs/btrfs/bio.c:135) btrfs_check_read_bio (fs/btrfs/bio.c:180 fs/btrfs/bio.c:285) simple_end_io_work process_one_work worker_thread Reject any segment whose payload would extend beyond compressed_len before copying it, treating it as corruption like the other on-disk validation failures in this function.

HighCVSS 7.5Not KEV-listedUpdated
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Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

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1CVSS vectors
3Timeline events
0ADP providers
4Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Linux

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2026-80631Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

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  2. CVE publishedCVE Program

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  3. CVE updatedCVE Program

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Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxa6e66e6f8c1b685e11b778bef614480a9c1a5278, a6e66e6f8c1b685e11b778bef614480a9c1a5278, a6e66e6f8c1b685e11b778bef614480a9c1a5278unaffected
LinuxLinux5.15, 0, 6.18.57, 7.1.5, 7.2affected
Weakness

CWE details

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