CentOS Linux 8.5 [TuxCare] 安全性更新：bpftool / kernel / kernel-core / kernel-cross-headers / etc 多個弱點 （CENTOS8.5：CLSA-2026：1786436146）
high Nessus Plugin ID 361319
語言:
概要
CentOS Linux 主機缺少一個或多個安全性更新。說明
CentOS Linux 8.5 主機已安裝的套件會受到 TuxCare CENTOS8.5：CLSA-2026：1786436146 公告中提及的多個弱點影響。- 已解決 Linux 核心中的下列弱點：bpf: Reject variable offset alu on PTR_TO_FLOW_KEYS For PTR_TO_FLOW_KEYS, check_flow_keys_access() only uses fixed off for validation.
However, variable offset ptr alu is not prohibited for this ptr kind. So the variable offset is not checked. The following prog is accepted: func#0 @0 0: R1=ctx() R10=fp0 0: (bf) r6 = r1 ; R1=ctx() R6_w=ctx() 1: (79) r7 = *(u64 *)(r6 +144) ; R6_w=ctx() R7_w=flow_keys() 2: (b7) r8 = 1024 ; R8_w=1024 3:
(37) r8 /= 1 ; R8_w=scalar() 4: (57) r8 &= 1024 ; R8_w=scalar(smin=smin32=0, smax=umax=smax32=umax32=1024,var_off=(0x0; 0x400)) 5: (0f) r7 += r8 mark_precise: frame0: last_idx 5 first_idx 0 subseq_idx -1 mark_precise: frame0: regs=r8 stack= before 4: (57) r8 &= 1024 mark_precise:
frame0: regs=r8 stack= before 3: (37) r8 /= 1 mark_precise: frame0: regs=r8 stack= before 2: (b7) r8 = 1024 6: R7_w=flow_keys(smin=smin32=0,smax=umax=smax32=umax32=1024,var_off =(0x0; 0x400)) R8_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=1024, var_off=(0x0; 0x400)) 6: (79) r0 = *(u64 *)(r7 +0) ; R0_w=scalar() 7: (95) exit This prog loads flow_keys to r7, and adds the variable offset r8 to r7, and finally causes out-of-bounds access: BUG: unable to handle page fault for address: ffffc90014c80038 [...] Call Trace: <TASK> bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline] __bpf_prog_run include/linux/filter.h:651 [inline] bpf_prog_run include/linux/filter.h:658 [inline] bpf_prog_run_pin_on_cpu include/linux/filter.h:675 [inline] bpf_flow_dissect+0x15f/0x350 net/core/flow_dissector.c:991 bpf_prog_test_run_flow_dissector+0x39d/0x620 net/bpf/test_run.c:1359 bpf_prog_test_run kernel/bpf/syscall.c:4107 [inline] __sys_bpf+0xf8f/0x4560 kernel/bpf/syscall.c:5475
__do_sys_bpf kernel/bpf/syscall.c:5561 [inline] __se_sys_bpf kernel/bpf/syscall.c:5559 [inline]
__x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:5559 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b Fix this by rejecting ptr alu with variable offset on flow_keys. Applying the patch rejects the program with R7 pointer arithmetic on flow_keys prohibited. (CVE-2024-26589)
- 已解決 Linux 核心中的下列弱點：netfilter: nf_conntrack_h323: fix OOB read in decode_choice() In decode_choice(), the boundary check before get_len() uses the variable `len`, which is still 0 from its initialization at the top of the function: unsigned int type, ext, len = 0; ...
if (ext || (son->attr & OPEN)) { BYTE_ALIGN(bs); if (nf_h323_error_boundary(bs, len, 0)) /* len is 0 here
*/ return H323_ERROR_BOUND; len = get_len(bs); /* OOB read */ When the bitstream is exactly consumed (bs->cur == bs->end), the check nf_h323_error_boundary(bs, 0, 0) evaluates to (bs->cur + 0 > bs->end), which is false. The subsequent get_len() call then dereferences *bs->cur++, reading 1 byte past the end of the buffer. If that byte has bit 7 set, get_len() reads a second byte as well. This can be triggered remotely by sending a crafted Q.931 SETUP message with a User-User Information Element containing exactly 2 bytes of PER-encoded data ({0x08, 0x00}) to port 1720 through a firewall with the nf_conntrack_h323 helper active. The decoder fully consumes the PER buffer before reaching this code path, resulting in a 1-2 byte heap-buffer-overflow read confirmed by AddressSanitizer. Fix this by checking for 2 bytes (the maximum that get_len() may read) instead of the uninitialized `len`. This matches the pattern used at every other get_len() call site in the same file, where the caller checks for 2 bytes of available data before calling get_len(). (CVE-2026-43233)
- 已解決 Linux 核心中的下列弱點：Bluetooth: SMP: force responder MITM requirements before building the pairing response smp_cmd_pairing_req() currently builds the pairing response from the initiator auth_req before enforcing the local BT_SECURITY_HIGH requirement. If the initiator omits SMP_AUTH_MITM, the response can also omit it even though the local side still requires MITM. tk_request() then sees an auth value without SMP_AUTH_MITM and may select JUST_CFM, making method selection inconsistent with the pairing policy the responder already enforces. When the local side requires HIGH security, first verify that MITM can be achieved from the IO capabilities and then force SMP_AUTH_MITM in the response in both rsp.auth_req and auth. This keeps the responder auth bits and later method selection aligned. (CVE-2026-43334)
- 已解決 Linux 核心中的下列弱點：ipv6: prevent possible UaF in addrconf_permanent_addr() The mentioned helper try to warn the user about an exceptional condition, but the message is delivered too late, accessing the ipv6 after its possible deletion. Reorder the statement to avoid the possible UaF; while at it, place the warning outside the idev->lock as it needs no protection. (CVE-2026-43339)
- 已解決 Linux 核心中的下列弱點：vsock: fix buffer size clamping order In vsock_update_buffer_size(), the buffer size was being clamped to the maximum first, and then to the minimum. If a user sets a minimum buffer size larger than the maximum, the minimum check overrides the maximum check, inverting the constraint. This breaks the intended socket memory boundaries by allowing the vsk->buffer_size to grow beyond the configured vsk->buffer_max_size. Fix this by checking the minimum first, and then the maximum. This ensures the buffer size never exceeds the buffer_max_size.
(CVE-2026-46234)
請注意，Nessus 並未測試這些問題，而是僅依據應用程式自我報告的版本號碼作出判斷。
解決方案
根據 TuxCare 公告 CENTOS8.5：CLSA-2026：1786436146 中的指引更新受影響的套件。另請參閱
Plugin 詳細資訊
嚴重性: High
ID: 361319
檔案名稱: tuxcare_centos_8.5_CLSA-2026-1786436146.nasl
版本: 1.1
類型: Local
代理程式: unix
已發布: 2026/10/1
已更新: 2026/10/1
支援的感應器: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus
風險資訊
VPR
風險因素: High
分數: 8
百分位數: 99.69
Vendor
Vendor Severity: Important
CVSS v2
風險因素: Medium
基本分數: 6.8
時間性分數: 5.3
媒介: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C
CVSS 評分資料來源: CVE-2026-53112
CVSS v3
風險因素: High
基本分數: 7.8
時間性分數: 7
媒介: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
時間媒介: CVSS:3.0/E:P/RL:O/RC:C
弱點資訊
必要的 KB 項目: Host/local_checks_enabled, Host/CentOS/release, Host/CentOS/rpm-list, Host/OS/extended-third-party
可被惡意程式利用: true
可輕鬆利用: Exploits are available
修補程式發佈日期: 2026/8/11
弱點發布日期: 2024/2/1
參考資訊
CVE: CVE-2024-26589, CVE-2026-43233, CVE-2026-43334, CVE-2026-43339, CVE-2026-46234, CVE-2026-53112, CVE-2026-64561
CLSA: 2026:1786436146