Linux Distros のパッチ未適用の脆弱性: CVE-2024-35949
high Nessus プラグイン ID 228679
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概要
Linux/Unix ホストには、ベンダーにより修正されていないことを示す脆弱性を持つ複数のパッケージがインストールされています。説明
Linux/Unix ホストには、ベンダーが提供するパッチが利用できない脆弱性の影響を受ける複数のパッケージがインストールされています。- Linux カーネルにおいて、以下の脆弱性は解決されました： btrfs: make sure that WRITTEN is set on all metadata blocks We previously would call btrfs_check_leaf() if we had the check integrity code enabled, which meant that we could only run the extended leaf checks if we had WRITTEN set on the header flags. This leaves a gap in our checking, because we could end up with corruption on disk where WRITTEN isn't set on the leaf, and then the extended leaf checks don't get run which we rely on to validate all of the item pointers to make sure we don't access memory outside of the extent buffer. However, since 732fab95abe2 (btrfs: check-integrity: remove CONFIG_BTRFS_FS_CHECK_INTEGRITY option) we no longer call btrfs_check_leaf() from btrfs_mark_buffer_dirty(), which means we only ever call it on blocks that are being written out, and thus have WRITTEN set, or that are being read in, which should have WRITTEN set.
Add checks to make sure we have WRITTEN set appropriately, and then make sure __btrfs_check_leaf() always does the item checking. This will protect us from file systems that have been corrupted and no longer have WRITTEN set on some of the blocks. This was hit on a crafted image tweaking the WRITTEN bit and reported by KASAN as out-of-bound access in the eb accessors. The example is a dir item at the end of an eb.
[2.042] BTRFS warning (device loop1): bad eb member start: ptr 0x3fff start 30572544 member offset 16410 size 2 [2.040] general protection fault, probably for non-canonical address 0xe0009d1000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI [2.537] KASAN: maybe wild-memory-access in range [0x0005088000000018-0x000508800000001f] [2.729] CPU: 0 PID: 2587 Comm: mount Not tainted 6.8.2 #1 [2.729] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 [2.621] RIP:
0010:btrfs_get_16+0x34b/0x6d0 [2.621] RSP: 0018:ffff88810871fab8 EFLAGS: 00000206 [2.621] RAX:
0000a11000000003 RBX: ffff888104ff8720 RCX: ffff88811b2288c0 [2.621] RDX: dffffc0000000000 RSI:
ffffffff81dd8aca RDI: ffff88810871f748 [2.621] RBP: 000000000000401a R08: 0000000000000001 R09:
ffffed10210e3ee9 [2.621] R10: ffff88810871f74f R11: 205d323430333737 R12: 000000000000001a [2.621] R13:
000508800000001a R14: 1ffff110210e3f5d R15: ffffffff850011e8 [2.621] FS: 00007f56ea275840(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000 [2.621] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [2.621] CR2: 00007febd13b75c0 CR3: 000000010bb50000 CR4: 00000000000006f0 [2.621] Call Trace: [2.621] <TASK> [2.621] ? show_regs+0x74/0x80 [2.621] ? die_addr+0x46/0xc0 [2.621] ? exc_general_protection+0x161/0x2a0 [2.621] ? asm_exc_general_protection+0x26/0x30 [2.621] ? btrfs_get_16+0x33a/0x6d0 [2.621] ? btrfs_get_16+0x34b/0x6d0 [2.621] ? btrfs_get_16+0x33a/0x6d0 [2.621] ?
__pfx_btrfs_get_16+0x10/0x10 [2.621] ? __pfx_mutex_unlock+0x10/0x10 [2.621] btrfs_match_dir_item_name+0x101/0x1a0 [2.621] btrfs_lookup_dir_item+0x1f3/0x280 [2.621] ?
__pfx_btrfs_lookup_dir_item+0x10/0x10 [2.621] btrfs_get_tree+0xd25/0x1910 [ copy more details from report] (CVE-2024-35949)
Nessus は、ベンダーによって報告されたパッケージの存在に依存していることに注意してください。
ソリューション
現時点で既知の解決策はありません。プラグインの詳細
深刻度: High
ID: 228679
ファイル名: unpatched_CVE_2024_35949.nasl
バージョン: 1.1
タイプ: local
エージェント: unix
ファミリー: Misc.
公開日: 2025/3/5
更新日: 2025/3/5
サポートされているセンサー: Nessus Agent, Nessus
リスク情報
VPR
リスクファクター: Medium
スコア: 6.7
CVSS v2
リスクファクター: Medium
基本値: 6.8
現状値: 5
ベクトル: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C
CVSS スコアのソース: CVE-2024-35949
CVSS v3
リスクファクター: High
基本値: 7.8
現状値: 6.8
ベクトル: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
現状ベクトル: CVSS:3.0/E:U/RL:O/RC:C
脆弱性情報
必要な KB アイテム: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched
エクスプロイトの容易さ: No known exploits are available
脆弱性公開日: 2024/5/18
参照情報
CVE: CVE-2024-35949