Answer in brief
CVE-2026-64417 records a Unknown severity vulnerability in mm: shrinker: fix NULL pointer dereference in debugfs. 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.
A CVSS score is not reported in the current record. 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 | >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <ebb45c2648b1f60715fd283700f651e05e431231 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <09d2407985b8ce3e831f9d4310fe7ac06a6b3ae9 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <36f8534f461222291a74156ab91f3ba9f09b6f93 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <006467ab932698612398f853344a7405164541f4 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <b9beed2322f3538b0d2d53307062da4102b8d8d8 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <e30453c61e185e914fde83c650e268067b140218 | ebb45c2648b1f60715fd283700f651e05e431231, 09d2407985b8ce3e831f9d4310fe7ac06a6b3ae9, 36f8534f461222291a74156ab91f3ba9f09b6f93, 006467ab932698612398f853344a7405164541f4, b9beed2322f3538b0d2d53307062da4102b8d8d8, e30453c61e185e914fde83c650e268067b140218 |
| Linux/Linuxgeneric | 6.0 | Not reported |
Published upstream
Jul 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 11, 2026
In the Linux kernel, the following vulnerability has been resolved: mm: shrinker: fix NULL pointer dereference in debugfs shrinker_debugfs_add() creates both "count" and "scan" debugfs files unconditionally. That assumes every shrinker implements both count_objects() and scan_objects(), which is not guaranteed. For example, the xen-backend shrinker sets count_objects() but leaves scan_objects() NULL, so writing to its scan file calls through a NULL function pointer and panics the kernel: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. Call Trace: <TASK> shrinker_debugfs_scan_write+0x12e/0x270 full_proxy_write+0x5f/0x90 vfs_write+0xde/0x420 ? filp_flush+0x75/0x90 ? filp_close+0x1d/0x30 ? do_dup2+0xb8/0x120 ksys_write+0x68/0xf0 ? filp_flush+0x75/0x90 do_syscall_64+0xb3/0x5b0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The count path has the same issue in principle if a shrinker omits count_objects(). To fix it, only create "count" and "scan" debugfs files when the corresponding callbacks are present.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-64417 records a Unknown severity vulnerability in mm: shrinker: fix NULL pointer dereference in debugfs. 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.
A CVSS score is not reported in the current record. 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 | >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <ebb45c2648b1f60715fd283700f651e05e431231 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <09d2407985b8ce3e831f9d4310fe7ac06a6b3ae9 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <36f8534f461222291a74156ab91f3ba9f09b6f93 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <006467ab932698612398f853344a7405164541f4 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <b9beed2322f3538b0d2d53307062da4102b8d8d8 || >=bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 <e30453c61e185e914fde83c650e268067b140218 | ebb45c2648b1f60715fd283700f651e05e431231, 09d2407985b8ce3e831f9d4310fe7ac06a6b3ae9, 36f8534f461222291a74156ab91f3ba9f09b6f93, 006467ab932698612398f853344a7405164541f4, b9beed2322f3538b0d2d53307062da4102b8d8d8, e30453c61e185e914fde83c650e268067b140218 |
| Linux/Linuxgeneric | 6.0 | Not reported |
Published upstream
Jul 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 11, 2026
In the Linux kernel, the following vulnerability has been resolved: mm: shrinker: fix NULL pointer dereference in debugfs shrinker_debugfs_add() creates both "count" and "scan" debugfs files unconditionally. That assumes every shrinker implements both count_objects() and scan_objects(), which is not guaranteed. For example, the xen-backend shrinker sets count_objects() but leaves scan_objects() NULL, so writing to its scan file calls through a NULL function pointer and panics the kernel: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. Call Trace: <TASK> shrinker_debugfs_scan_write+0x12e/0x270 full_proxy_write+0x5f/0x90 vfs_write+0xde/0x420 ? filp_flush+0x75/0x90 ? filp_close+0x1d/0x30 ? do_dup2+0xb8/0x120 ksys_write+0x68/0xf0 ? filp_flush+0x75/0x90 do_syscall_64+0xb3/0x5b0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The count path has the same issue in principle if a shrinker omits count_objects(). To fix it, only create "count" and "scan" debugfs files when the corresponding callbacks are present.
Quoted source text, attributed separately from HOL analysis.