In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double free of TCP_Server_Info::hostname When shutting down the server in cifs_put_tcp_session(), cifsd thread might be reconnecting to multiple DFS targets before it realizes it should exit the loop, so @server->hostname can't be freed as long as cifsd thread isn't done. Otherwise the following can happen: RIP: 0010:__slab_free+0x223/0x3c0 Code: 5e 41 5f c3 cc cc cc cc 4c 89 de 4c 89 cf 44 89 44 24 08 4c 89 1c 24 e8 fb cf 8e 00 44 8b 44 24 08 4c 8b 1c 24 e9 5f fe ff ff <0f> 0b 41 f7 45 08 00 0d 21 00 0f 85 2d ff ff ff e9 1f ff ff ff 80 RSP: 0018:ffffb26180dbfd08 EFLAGS: 00010246 RAX: ffff8ea34728e510 RBX: ffff8ea34728e500 RCX: 0000000000800068 RDX: 0000000000800068 RSI: 0000000000000000 RDI: ffff8ea340042400 RBP: ffffe112041ca380 R08: 0000000000000001 R09: 0000000000000000 R10: 6170732e31303000 R11: 70726f632e786563 R12: ffff8ea34728e500 R13: ffff8ea340042400 R14: ffff8ea34728e500 R15: 0000000000800068 FS: 0000000000000000(0000) GS:ffff8ea66fd80000(0000) 000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc25376080 CR3: 000000012a2ba001 CR4: PKRU: 55555554 Call Trace: <TASK> ? show_trace_log_lvl+0x1c4/0x2df ? show_trace_log_lvl+0x1c4/0x2df ? __reconnect_target_unlocked+0x3e/0x160 [cifs] ? __die_body.cold+0x8/0xd ? die+0x2b/0x50 ? do_trap+0xce/0x120 ? __slab_free+0x223/0x3c0 ? do_error_trap+0x65/0x80 ? __slab_free+0x223/0x3c0 ? exc_invalid_op+0x4e/0x70 ? __slab_free+0x223/0x3c0 ? asm_exc_invalid_op+0x16/0x20 ? __slab_free+0x223/0x3c0 ? extract_hostname+0x5c/0xa0 [cifs] ? extract_hostname+0x5c/0xa0 [cifs] ? __kmalloc+0x4b/0x140 __reconnect_target_unlocked+0x3e/0x160 [cifs] reconnect_dfs_server+0x145/0x430 [cifs] cifs_handle_standard+0x1ad/0x1d0 [cifs] cifs_demultiplex_thread+0x592/0x730 [cifs] ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] kthread+0xdd/0x100 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x29/0x50 </TASK>
総合評価: CVE-2025-21673 は低リスク（25.3/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 0.19%、9 パーセンタイル） 推奨対応: 悪用情報と EPSS の推移を監視し、必要に応じて優先度を見直してください。
リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。
EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置（高いほど相対的に深刻）を示します。
| # | 日付 | 旧 EPSS スコア | 新 EPSS スコア | Δ（新 − 旧） |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.03% | 0.19% | +0.16% |
| 2 | 2025-11-21 | 0.06% | 0.03% | -0.03% |
| 3 | 2025-11-18 | — | 0.06% | — |
EPSS の全履歴 （全 4 件）
この CVE の CVSS 指標。
| ベーススコア | バージョン | 深刻度 | ベクトル | 悪用しやすさ | 影響 | スコアの出典 |
|---|---|---|---|---|---|---|
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | [email protected] |
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
unimportant | CVE-2025-21673 unimportant priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. | https://security-tracker.debian.org/tracker/CVE-2025-21673 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2025-21673 |
suse
|
medium | CVE-2025-21673 severity moderate: SUSE including 428 source package names (2.1.3-6.11:kernel-default-6.4.0-28.1, 2.1.3-6.12:kernel-default-base-6.4.0-28.1.21.6, …), 701 product×package rows across 129 product lines (Container suse/sl-micro/6.0/base-os-container, Container suse/sl-micro/6.0/kvm-os-container, … (129 product lines)): Fixed 435, Known Affected 231, Known Not Affected 35. | https://www.suse.com/security/cve/CVE-2025-21673/ |
ubuntu
|
medium | CVE-2025-21673 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 148, released 148, not-affected 74, needed 36. | https://ubuntu.com/security/CVE-2025-21673 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| linux | linux_kernel | >= 5.14.19, < 5.15 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.15.3, < 6.6.74 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.7, < 6.12.11 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | 6.13 | cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* |
| linux | linux_kernel | 6.13 | cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:* |
| linux | linux_kernel | 6.13 | cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:* |
| linux | linux_kernel | 6.13 | cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:* |
| linux | linux_kernel | 6.13 | cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:* |
| linux | linux_kernel | 6.13 | cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:* |
| linux | linux_kernel | 6.13 | cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:* |