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CVE-2025-21851— bpf: Fix softlockup in arena_map_free on 64k page kernel

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞,该漏洞源于arena_map_free在64k页内核上可能导致软锁。

CVSS 7.8 · High EPSS 0.18% · P7

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 8

VendorProduct Version RangeStatus
Linux Linux 317460317a02a1af512697e6e964298dedd8a163< c1f3f3892d4526f18aaeffdb6068ce861e793ee3 affected
317460317a02a1af512697e6e964298dedd8a163< 787d556a3de447e70964a4bdeba9196f62a62b1e affected
317460317a02a1af512697e6e964298dedd8a163< 517e8a7835e8cfb398a0aeb0133de50e31cae32b affected
6.9 affected
< 6.9 unaffected
6.12.17≤ 6.12.* unaffected
6.13.5≤ 6.13.* unaffected
6.14≤ * unaffected
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I. Basic Information for CVE-2025-21851

Vulnerability Information

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Vulnerability Title
bpf: Fix softlockup in arena_map_free on 64k page kernel
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix softlockup in arena_map_free on 64k page kernel On an aarch64 kernel with CONFIG_PAGE_SIZE_64KB=y, arena_htab tests cause a segmentation fault and soft lockup. The same failure is not observed with 4k pages on aarch64. It turns out arena_map_free() is calling apply_to_existing_page_range() with the address returned by bpf_arena_get_kern_vm_start(). If this address is not page-aligned the code ends up calling apply_to_pte_range() with that unaligned address causing soft lockup. Fix it by round up GUARD_SZ to PAGE_SIZE << 1 so that the division by 2 in bpf_arena_get_kern_vm_start() returns a page-aligned value.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞,该漏洞源于arena_map_free在64k页内核上可能导致软锁。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 317460317a02a1af512697e6e964298dedd8a163 ~ c1f3f3892d4526f18aaeffdb6068ce861e793ee3 -
Linux Linux 6.9 -

II. Public POCs for CVE-2025-21851

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III. Intelligence Information for CVE-2025-21851

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Other References for CVE-2025-21851 (3)

Same Patch Batch · Linux · 2025-03-12 · 26 CVEs total

CVE-2024-58087 9.8 CRITICAL ksmbd: fix racy issue from session lookup and expire
CVE-2025-21850 9.8 CRITICAL nvmet: Fix crash when a namespace is disabled
CVE-2025-21855 8.6 HIGH ibmvnic: Don't reference skb after sending to VIOS
CVE-2024-58089 7.8 HIGH btrfs: fix double accounting race when btrfs_run_delalloc_range() failed
CVE-2025-21858 7.8 HIGH geneve: Fix use-after-free in geneve_find_dev().
CVE-2025-21864 7.8 HIGH tcp: drop secpath at the same time as we currently drop dst
CVE-2025-21844 7.5 HIGH smb: client: Add check for next_buffer in receive_encrypted_standard()
CVE-2025-21852 net: Add rx_skb of kfree_skb to raw_tp_null_args[].
CVE-2025-21865 gtp: Suppress list corruption splat in gtp_net_exit_batch_rtnl().
CVE-2024-58088 bpf: Fix deadlock when freeing cgroup storage
CVE-2025-21845 mtd: spi-nor: sst: Fix SST write failure
CVE-2025-21846 acct: perform last write from workqueue
CVE-2025-21848 nfp: bpf: Add check for nfp_app_ctrl_msg_alloc()
CVE-2025-21847 ASoC: SOF: stream-ipc: Check for cstream nullity in sof_ipc_msg_data()
CVE-2025-21849 drm/i915/gt: Use spin_lock_irqsave() in interruptible context
CVE-2025-21863 io_uring: prevent opcode speculation
CVE-2025-21853 bpf: avoid holding freeze_mutex during mmap operation
CVE-2025-21866 powerpc/code-patching: Fix KASAN hit by not flagging text patching area as VM_ALLOC
CVE-2025-21854 sockmap, vsock: For connectible sockets allow only connected
CVE-2025-21856 s390/ism: add release function for struct device

Showing top 20 of 26 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities