[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"repo-stars":3,"vuln-DEBIAN-CVE-2021-47089":6},{"stargazers_count":4,"fetched_at":5},7,"2026-06-04T02:53:27.892Z",{"id":7,"descriptions":8,"cisa":9,"weaknesses":10,"exploits":11,"aliases":12,"duplicate_of":9,"upstream":13,"downstream":16,"duplicates":17,"related":18,"reserved_at":9,"published_at":19,"modified_at":20,"state":9,"summary":21,"references_raw":23,"kevs":30,"epss":9,"epss_history":31,"metrics":32,"affected":39},"DEBIAN-CVE-2021-47089","In the Linux kernel, the following vulnerability has been resolved:  kfence: fix memory leak when cat kfence objects  Hulk robot reported a kmemleak problem:      unreferenced object 0xffff93d1d8cc02e8 (size 248):       comm \"cat\", pid 23327, jiffies 4624670141 (age 495992.217s)       hex dump (first 32 bytes):         00 40 85 19 d4 93 ff ff 00 10 00 00 00 00 00 00  .@..............         00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................       backtrace:          seq_open+0x2a/0x80          full_proxy_open+0x167/0x1e0          do_dentry_open+0x1e1/0x3a0          path_openat+0x961/0xa20          do_filp_open+0xae/0x120          do_sys_openat2+0x216/0x2f0          do_sys_open+0x57/0x80          do_syscall_64+0x33/0x40          entry_SYSCALL_64_after_hwframe+0x44/0xa9     unreferenced object 0xffff93d419854000 (size 4096):       comm \"cat\", pid 23327, jiffies 4624670141 (age 495992.217s)       hex dump (first 32 bytes):         6b 66 65 6e 63 65 2d 23 32 35 30 3a 20 30 78 30  kfence-#250: 0x0         30 30 30 30 30 30 30 37 35 34 62 64 61 31 32 2d  0000000754bda12-       backtrace:          seq_read_iter+0x313/0x440          seq_read+0x14b/0x1a0          full_proxy_read+0x56/0x80          vfs_read+0xa5/0x1b0          ksys_read+0xa0/0xf0          do_syscall_64+0x33/0x40          entry_SYSCALL_64_after_hwframe+0x44/0xa9  I find that we can easily reproduce this problem with the following commands:  \tcat /sys/kernel/debug/kfence/objects \techo scan > /sys/kernel/debug/kmemleak \tcat /sys/kernel/debug/kmemleak  The leaked memory is allocated in the stack below:      do_syscall_64       do_sys_open         do_dentry_open           full_proxy_open             seq_open            ---> alloc seq_file       vfs_read         full_proxy_read           seq_read             seq_read_iter               traverse          ---> alloc seq_buf  And it should have been released in the following process:      do_syscall_64       syscall_exit_to_user_mode         exit_to_user_mode_prepare           task_work_run             ____fput               __fput                 full_proxy_release  ---> free here  However, the release function corresponding to file_operations is not implemented in kfence.  As a result, a memory leak occurs.  Therefore, the solution to this problem is to implement the corresponding release function.",null,[],[],[],[14],{"_key":15},"CVE-2021-47089",[],[],[],"2024-03-04T18:15:07.560Z","2026-04-28T20:23:18.982364Z",{"cisa_kev":22,"cisa_ransomware":22,"cisa_vendor":9,"epss_severity":9,"epss_score":9,"severity":9,"severity_score":9,"severity_version":9,"severity_source":9,"severity_vector":9,"severity_status":9},false,[24],{"url":25,"sources":26,"tags":28},"https://security-tracker.debian.org/tracker/CVE-2021-47089",[27],"osv_debian",[29],"Advisory",[],[],[33],{"source":27,"cvss_v2_0":9,"cvss_v3_0":9,"cvss_v3_1":34,"cvss_v4_0":9},{"baseScore":35,"baseSeverity":9,"vectorString":36,"impactScore":37,"exploitabilityScore":38},3.3,"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",2.3,4.6,[40],{"ecosystem":41,"name":42,"vendor":43,"product":42,"cpe_part":9,"purl_type":44,"purl_namespace":43,"purl_name":42,"source":9,"versions":45},"Debian","linux","debian","deb",[46,52,53],{"version":47,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":50,"version_end_type":51,"fixed_in":9},"lt5_15_15_1",true,"ecosystem","5.15.15-1","excluding",{"version":47,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":50,"version_end_type":51,"fixed_in":9},{"version":47,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":50,"version_end_type":51,"fixed_in":9}]