Answer in brief
CVE-2026-64426 records a Unknown severity vulnerability in io_uring/nop: fix file reference leak with IOSQE_FIXED_FILE. 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 | >=a85f31052bce52111b4e9d5a536003481d0421d0 <722869fcff598fad20d5ab79c305897a7534708b || >=a85f31052bce52111b4e9d5a536003481d0421d0 <7267717f35787167fcce4bc14f6ef3fa06682dcf || >=a85f31052bce52111b4e9d5a536003481d0421d0 <2564ca2e31bd8ee8348362941af2ee4671e487ca | 722869fcff598fad20d5ab79c305897a7534708b, 7267717f35787167fcce4bc14f6ef3fa06682dcf, 2564ca2e31bd8ee8348362941af2ee4671e487ca |
| Linux/Linuxgeneric | 6.13 | 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: io_uring/nop: fix file reference leak with IOSQE_FIXED_FILE NOP file-acquisition support choses between a fixed (registered) file and a normal fget()'d file based on its own IORING_NOP_FIXED_FILE flag in sqe->nop_flags. However, a request's REQ_F_FIXED_FILE is set independently from the generic IOSQE_FIXED_FILE sqe flag during request init, before the issue handler runs. If a NOP is submitted with IOSQE_FIXED_FILE set (so REQ_F_FIXED_FILE is set) but without IORING_NOP_FIXED_FILE, io_nop() takes the normal path and grabs a real reference via io_file_get_normal(). On completion, io_put_file() only drops the reference when REQ_F_FIXED_FILE is clear, so the fget()'d file is never released and leaks: BUG: memory leak unreferenced object 0xffff88800f42c240 (size 176): kmem_cache_alloc_noprof+0x358/0x440 alloc_empty_file+0x57/0x180 path_openat+0x44/0x1e50 do_file_open+0x121/0x200 do_sys_openat2+0xa7/0x150 __x64_sys_openat+0x82/0xf0 Decide between fixed and normal file acquisition from REQ_F_FIXED_FILE, the same way io_assign_file() does for every other opcode, and fold IORING_NOP_FIXED_FILE into REQ_F_FIXED_FILE at prep time.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-64426 records a Unknown severity vulnerability in io_uring/nop: fix file reference leak with IOSQE_FIXED_FILE. 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 | >=a85f31052bce52111b4e9d5a536003481d0421d0 <722869fcff598fad20d5ab79c305897a7534708b || >=a85f31052bce52111b4e9d5a536003481d0421d0 <7267717f35787167fcce4bc14f6ef3fa06682dcf || >=a85f31052bce52111b4e9d5a536003481d0421d0 <2564ca2e31bd8ee8348362941af2ee4671e487ca | 722869fcff598fad20d5ab79c305897a7534708b, 7267717f35787167fcce4bc14f6ef3fa06682dcf, 2564ca2e31bd8ee8348362941af2ee4671e487ca |
| Linux/Linuxgeneric | 6.13 | 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: io_uring/nop: fix file reference leak with IOSQE_FIXED_FILE NOP file-acquisition support choses between a fixed (registered) file and a normal fget()'d file based on its own IORING_NOP_FIXED_FILE flag in sqe->nop_flags. However, a request's REQ_F_FIXED_FILE is set independently from the generic IOSQE_FIXED_FILE sqe flag during request init, before the issue handler runs. If a NOP is submitted with IOSQE_FIXED_FILE set (so REQ_F_FIXED_FILE is set) but without IORING_NOP_FIXED_FILE, io_nop() takes the normal path and grabs a real reference via io_file_get_normal(). On completion, io_put_file() only drops the reference when REQ_F_FIXED_FILE is clear, so the fget()'d file is never released and leaks: BUG: memory leak unreferenced object 0xffff88800f42c240 (size 176): kmem_cache_alloc_noprof+0x358/0x440 alloc_empty_file+0x57/0x180 path_openat+0x44/0x1e50 do_file_open+0x121/0x200 do_sys_openat2+0xa7/0x150 __x64_sys_openat+0x82/0xf0 Decide between fixed and normal file acquisition from REQ_F_FIXED_FILE, the same way io_assign_file() does for every other opcode, and fold IORING_NOP_FIXED_FILE into REQ_F_FIXED_FILE at prep time.
Quoted source text, attributed separately from HOL analysis.