Answer in brief
CVE-2021-47124 records a High severity (CVSS 7.8) vulnerability in io_uring: fix link timeout refs. 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.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1c20e9040f49687ba2ccc2ffd4411351a6c2ebff <0b2a990e5d2f76d020cb840c456e6ec5f0c27530 || >=1c20e9040f49687ba2ccc2ffd4411351a6c2ebff <6f5d7a45f58d3abe3a936de1441b8d6318f978ff || >=9ae1f8dd372e0e4c020b345cf9e09f519265e981 <876808dba2ff7509bdd7f230c4f374a0caf4f410 || >=9ae1f8dd372e0e4c020b345cf9e09f519265e981 <ff4a96ba5c8f9b266706280ff8021d2ef3f17e86 || >=9ae1f8dd372e0e4c020b345cf9e09f519265e981 <a298232ee6b9a1d5d732aa497ff8be0d45b5bd82 || 567c81912cec641db75ac6cb64c63f8367c97d19 || >=5.10.26 <5.10.43 || >=5.10.26 <5.10.55 || >=5.11.6 <5.12 | 0b2a990e5d2f76d020cb840c456e6ec5f0c27530, 6f5d7a45f58d3abe3a936de1441b8d6318f978ff, 876808dba2ff7509bdd7f230c4f374a0caf4f410, ff4a96ba5c8f9b266706280ff8021d2ef3f17e86, a298232ee6b9a1d5d732aa497ff8be0d45b5bd82, 5.10.43, 5.10.55, 5.12 |
| Linux/Linuxgeneric | 5.12 | Not reported |
Published upstream
Mar 15, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 4, 2026
In the Linux kernel, the following vulnerability has been resolved: io_uring: fix link timeout refs WARNING: CPU: 0 PID: 10242 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 RIP: 0010:refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 Call Trace: __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] io_put_req fs/io_uring.c:2140 [inline] io_queue_linked_timeout fs/io_uring.c:6300 [inline] __io_queue_sqe+0xbef/0xec0 fs/io_uring.c:6354 io_submit_sqe fs/io_uring.c:6534 [inline] io_submit_sqes+0x2bbd/0x7c50 fs/io_uring.c:6660 __do_sys_io_uring_enter fs/io_uring.c:9240 [inline] __se_sys_io_uring_enter+0x256/0x1d60 fs/io_uring.c:9182 io_link_timeout_fn() should put only one reference of the linked timeout request, however in case of racing with the master request's completion first io_req_complete() puts one and then io_put_req_deferred() is called.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2021-47124 records a High severity (CVSS 7.8) vulnerability in io_uring: fix link timeout refs. 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.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1c20e9040f49687ba2ccc2ffd4411351a6c2ebff <0b2a990e5d2f76d020cb840c456e6ec5f0c27530 || >=1c20e9040f49687ba2ccc2ffd4411351a6c2ebff <6f5d7a45f58d3abe3a936de1441b8d6318f978ff || >=9ae1f8dd372e0e4c020b345cf9e09f519265e981 <876808dba2ff7509bdd7f230c4f374a0caf4f410 || >=9ae1f8dd372e0e4c020b345cf9e09f519265e981 <ff4a96ba5c8f9b266706280ff8021d2ef3f17e86 || >=9ae1f8dd372e0e4c020b345cf9e09f519265e981 <a298232ee6b9a1d5d732aa497ff8be0d45b5bd82 || 567c81912cec641db75ac6cb64c63f8367c97d19 || >=5.10.26 <5.10.43 || >=5.10.26 <5.10.55 || >=5.11.6 <5.12 | 0b2a990e5d2f76d020cb840c456e6ec5f0c27530, 6f5d7a45f58d3abe3a936de1441b8d6318f978ff, 876808dba2ff7509bdd7f230c4f374a0caf4f410, ff4a96ba5c8f9b266706280ff8021d2ef3f17e86, a298232ee6b9a1d5d732aa497ff8be0d45b5bd82, 5.10.43, 5.10.55, 5.12 |
| Linux/Linuxgeneric | 5.12 | Not reported |
Published upstream
Mar 15, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 4, 2026
In the Linux kernel, the following vulnerability has been resolved: io_uring: fix link timeout refs WARNING: CPU: 0 PID: 10242 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 RIP: 0010:refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28 Call Trace: __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] io_put_req fs/io_uring.c:2140 [inline] io_queue_linked_timeout fs/io_uring.c:6300 [inline] __io_queue_sqe+0xbef/0xec0 fs/io_uring.c:6354 io_submit_sqe fs/io_uring.c:6534 [inline] io_submit_sqes+0x2bbd/0x7c50 fs/io_uring.c:6660 __do_sys_io_uring_enter fs/io_uring.c:9240 [inline] __se_sys_io_uring_enter+0x256/0x1d60 fs/io_uring.c:9182 io_link_timeout_fn() should put only one reference of the linked timeout request, however in case of racing with the master request's completion first io_req_complete() puts one and then io_put_req_deferred() is called.
Quoted source text, attributed separately from HOL analysis.