Answer in brief
CVE-2026-64416 records a Unknown severity vulnerability in mm: swap_cgroup: fix NULL deref in lookup_swap_cgroup_id on swapless host. 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 | >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <818416fef38759f23210de449663cd9d7e293d39 || >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <b415c00bf23df577a4a95673d00ae76687bcc1d4 || >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <6a4196d19f477524d2f92adca90fc1fbe9a0420a || >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <63b02a9409cb5180398491b093e48bcb5315f5fb | 818416fef38759f23210de449663cd9d7e293d39, b415c00bf23df577a4a95673d00ae76687bcc1d4, 6a4196d19f477524d2f92adca90fc1fbe9a0420a, 63b02a9409cb5180398491b093e48bcb5315f5fb |
| Linux/Linuxgeneric | 6.12 | 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: swap_cgroup: fix NULL deref in lookup_swap_cgroup_id on swapless host lookup_swap_cgroup_id() passes swap_cgroup_ctrl[type].map to __swap_cgroup_id_lookup() without checking that the type was ever registered via swap_cgroup_swapon(). On a swapless host every ctrl->map is NULL, so __swap_cgroup_id_lookup() dereferences NULL + a scaled swp_offset(). Since commit bea67dcc5eea ("mm: attempt to batch free swap entries for zap_pte_range()"), zap_pte_range() -> swap_pte_batch() calls lookup_swap_cgroup_id() on any non-present, non-none PTE that decodes as a real swap entry, without first validating it against swap_info[]. A single PTE corrupted into a type-0 swap entry takes the host down at process exit. We hit this in production on a swapless 6.12.58 host: ~1s of "get_swap_device: Bad swap file entry 3f800204222bb" (do_swap_page() being correctly defensive about the same entry) followed by BUG: unable to handle page fault for address: 000003f800204220 RIP: 0010:lookup_swap_cgroup_id+0x2b/0x60 Call Trace: swap_pte_batch+0xbf/0x230 zap_pte_range+0x4c8/0x780 unmap_page_range+0x190/0x3e0 exit_mmap+0xd9/0x3c0 do_exit+0x20c/0x4b0 syzbot has reported the identical stack. The source of the PTE corruption is a separate bug; this change makes the teardown path as robust as the fault path already is. Every other caller of lookup_swap_cgroup_id() is downstream of a get_swap_device() that has already validated the entry, so the new branch is cold.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-64416 records a Unknown severity vulnerability in mm: swap_cgroup: fix NULL deref in lookup_swap_cgroup_id on swapless host. 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 | >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <818416fef38759f23210de449663cd9d7e293d39 || >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <b415c00bf23df577a4a95673d00ae76687bcc1d4 || >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <6a4196d19f477524d2f92adca90fc1fbe9a0420a || >=bea67dcc5eea0f6a213897a59b9e644977cd07e6 <63b02a9409cb5180398491b093e48bcb5315f5fb | 818416fef38759f23210de449663cd9d7e293d39, b415c00bf23df577a4a95673d00ae76687bcc1d4, 6a4196d19f477524d2f92adca90fc1fbe9a0420a, 63b02a9409cb5180398491b093e48bcb5315f5fb |
| Linux/Linuxgeneric | 6.12 | 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: swap_cgroup: fix NULL deref in lookup_swap_cgroup_id on swapless host lookup_swap_cgroup_id() passes swap_cgroup_ctrl[type].map to __swap_cgroup_id_lookup() without checking that the type was ever registered via swap_cgroup_swapon(). On a swapless host every ctrl->map is NULL, so __swap_cgroup_id_lookup() dereferences NULL + a scaled swp_offset(). Since commit bea67dcc5eea ("mm: attempt to batch free swap entries for zap_pte_range()"), zap_pte_range() -> swap_pte_batch() calls lookup_swap_cgroup_id() on any non-present, non-none PTE that decodes as a real swap entry, without first validating it against swap_info[]. A single PTE corrupted into a type-0 swap entry takes the host down at process exit. We hit this in production on a swapless 6.12.58 host: ~1s of "get_swap_device: Bad swap file entry 3f800204222bb" (do_swap_page() being correctly defensive about the same entry) followed by BUG: unable to handle page fault for address: 000003f800204220 RIP: 0010:lookup_swap_cgroup_id+0x2b/0x60 Call Trace: swap_pte_batch+0xbf/0x230 zap_pte_range+0x4c8/0x780 unmap_page_range+0x190/0x3e0 exit_mmap+0xd9/0x3c0 do_exit+0x20c/0x4b0 syzbot has reported the identical stack. The source of the PTE corruption is a separate bug; this change makes the teardown path as robust as the fault path already is. Every other caller of lookup_swap_cgroup_id() is downstream of a get_swap_device() that has already validated the entry, so the new branch is cold.
Quoted source text, attributed separately from HOL analysis.