Answer in brief
CVE-2026-46107 records a High severity (CVSS 7.8) vulnerability in dm-thin: fix metadata refcount underflow. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-46107 records a High severity (CVSS 7.8) vulnerability in dm-thin: fix metadata refcount underflow. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <b719d12cb94df345e9ad2715fd0abe9afcaeb111 || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <f49b41c9eb7c6ff00df27cd49cea210abbadd8ad || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <f06f6aededd792a754cd677c02b3d3016d868c2c || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <12161e03d33afce781f68fa11cc6060538862fad || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <323d252a4a378834e4fe68298ca61cfc5dd3a460 || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <85311a585a26640760cd0f3349ab9f2905691044 || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <5ec0debbcfd43596e32c1239e993de06a704e04c || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <09a65adc7d8bbfce06392cb6d375468e2728ead5 | b719d12cb94df345e9ad2715fd0abe9afcaeb111, f49b41c9eb7c6ff00df27cd49cea210abbadd8ad, f06f6aededd792a754cd677c02b3d3016d868c2c, 12161e03d33afce781f68fa11cc6060538862fad, 323d252a4a378834e4fe68298ca61cfc5dd3a460, 85311a585a26640760cd0f3349ab9f2905691044, 5ec0debbcfd43596e32c1239e993de06a704e04c, 09a65adc7d8bbfce06392cb6d375468e2728ead5 |
| Linux/Linuxgeneric | 3.2 | Not reported |
Published upstream
May 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 19, 2026
In the Linux kernel, the following vulnerability has been resolved: dm-thin: fix metadata refcount underflow There's a bug in dm-thin in the function rebalance_children. If the internal btree node has one entry, the code tries to copy all btree entries from the node's child to the node itself and then decrement the child's reference count. If the child node is shared (it has reference count > 1), we won't free it, so there would be two pointers to each of the grandchildren nodes. But the reference counts of the grandchildren is not increased, thus the reference count doesn't match the number of pointers that point to the grandchildren. This results in "device mapper: space map common: unable to decrement block" errors. Fix this bug by incrementing reference counts on the grandchildren if the btree node is shared.
Quoted source text, attributed separately from HOL analysis.
CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <b719d12cb94df345e9ad2715fd0abe9afcaeb111 || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <f49b41c9eb7c6ff00df27cd49cea210abbadd8ad || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <f06f6aededd792a754cd677c02b3d3016d868c2c || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <12161e03d33afce781f68fa11cc6060538862fad || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <323d252a4a378834e4fe68298ca61cfc5dd3a460 || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <85311a585a26640760cd0f3349ab9f2905691044 || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <5ec0debbcfd43596e32c1239e993de06a704e04c || >=3241b1d3e0aaafbfcd320f4d71ade629728cc4f4 <09a65adc7d8bbfce06392cb6d375468e2728ead5 | b719d12cb94df345e9ad2715fd0abe9afcaeb111, f49b41c9eb7c6ff00df27cd49cea210abbadd8ad, f06f6aededd792a754cd677c02b3d3016d868c2c, 12161e03d33afce781f68fa11cc6060538862fad, 323d252a4a378834e4fe68298ca61cfc5dd3a460, 85311a585a26640760cd0f3349ab9f2905691044, 5ec0debbcfd43596e32c1239e993de06a704e04c, 09a65adc7d8bbfce06392cb6d375468e2728ead5 |
| Linux/Linuxgeneric | 3.2 | Not reported |
Published upstream
May 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 19, 2026
In the Linux kernel, the following vulnerability has been resolved: dm-thin: fix metadata refcount underflow There's a bug in dm-thin in the function rebalance_children. If the internal btree node has one entry, the code tries to copy all btree entries from the node's child to the node itself and then decrement the child's reference count. If the child node is shared (it has reference count > 1), we won't free it, so there would be two pointers to each of the grandchildren nodes. But the reference counts of the grandchildren is not increased, thus the reference count doesn't match the number of pointers that point to the grandchildren. This results in "device mapper: space map common: unable to decrement block" errors. Fix this bug by incrementing reference counts on the grandchildren if the btree node is shared.
Quoted source text, attributed separately from HOL analysis.