[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"repo-stars":3,"vuln-DEBIAN-CVE-2021-4454":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-2021-4454","In the Linux kernel, the following vulnerability has been resolved:  can: j1939: fix errant WARN_ON_ONCE in j1939_session_deactivate  The conclusion \"j1939_session_deactivate() should be called with a session ref-count of at least 2\" is incorrect. In some concurrent scenarios, j1939_session_deactivate can be called with the session ref-count less than 2. But there is not any problem because it will check the session active state before session putting in j1939_session_deactivate_locked().  Here is the concurrent scenario of the problem reported by syzbot and my reproduction log.          cpu0                            cpu1                                 j1939_xtp_rx_eoma j1939_xtp_rx_abort_one                                 j1939_session_get_by_addr [kref == 2] j1939_session_get_by_addr [kref == 3] j1939_session_deactivate [kref == 2] j1939_session_put [kref == 1] \t\t\t\tj1939_session_completed \t\t\t\tj1939_session_deactivate \t\t\t\tWARN_ON_ONCE(kref \u003C 2)  ===================================================== WARNING: CPU: 1 PID: 21 at net/can/j1939/transport.c:1088 j1939_session_deactivate+0x5f/0x70 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 5.14.0-rc7+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014 RIP: 0010:j1939_session_deactivate+0x5f/0x70 Call Trace:  j1939_session_deactivate_activate_next+0x11/0x28  j1939_xtp_rx_eoma+0x12a/0x180  j1939_tp_recv+0x4a2/0x510  j1939_can_recv+0x226/0x380  can_rcv_filter+0xf8/0x220  can_receive+0x102/0x220  ? process_backlog+0xf0/0x2c0  can_rcv+0x53/0xf0  __netif_receive_skb_one_core+0x67/0x90  ? process_backlog+0x97/0x2c0  __netif_receive_skb+0x22/0x80",null,[],[],[],[14],{"_key":15},"CVE-2021-4454",[],[],[],"2025-03-27T17:15:35.820Z","2026-04-28T20:23:07.600933Z",{"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-2021-4454",[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},5.5,"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",6,4.6,[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",[46,52,55,56],{"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_10_178_1",true,"ecosystem","5.10.178-1","excluding",{"version":53,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":54,"version_end_type":51,"fixed_in":9},"lt6_1_11_1","6.1.11-1",{"version":53,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":54,"version_end_type":51,"fixed_in":9},{"version":53,"is_range":48,"range_type":49,"version_start":9,"version_start_type":9,"version_end":54,"version_end_type":51,"fixed_in":9}]