cbcvebase.
CVE-2025-21881
published 2025-03-27

CVE-2025-21881: In the Linux kernel, the following vulnerability has been resolved: uprobes: Reject the shared zeropage in uprobe_write_opcode() We triggered the following…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.19%
9.4th percentile
In the Linux kernel, the following vulnerability has been resolved: uprobes: Reject the shared zeropage in uprobe_write_opcode() We triggered the following crash in syzkaller tests: BUG: Bad page state in process syz.7.38 pfn:1eff3 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1eff3 flags: 0x3fffff00004004(referenced|reserved|node=0|zone=1|lastcpupid=0x1fffff) raw: 003fffff00004004 ffffe6c6c07bfcc8 ffffe6c6c07bfcc8 0000000000000000 raw: 0000000000000000 0000000000000000 00000000fffffffe 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: dump_stack_lvl+0x32/0x50 bad_page+0x69/0xf0 free_unref_page_prepare+0x401/0x500 free_unref_page+0x6d/0x1b0 uprobe_write_opcode+0x460/0x8e0 install_breakpoint.part.0+0x51/0x80 register_for_each_vma+0x1d9/0x2b0 __uprobe_register+0x245/0x300 bpf_uprobe_multi_link_attach+0x29b/0x4f0 link_create+0x1e2/0x280 __sys_bpf+0x75f/0xac0 __x64_sys_bpf+0x1a/0x30 do_syscall_64+0x56/0x100 entry_SYSCALL_64_after_hwframe+0x78/0xe2 BUG: Bad rss-counter state mm:00000000452453e0 type:MM_FILEPAGES val:-1 The following syzkaller test case can be used to reproduce: r2 = creat(&(0x7f0000000000)='./file0\x00', 0x8) write$nbd(r2, &(0x7f0000000580)=ANY=[], 0x10) r4 = openat(0xffffffffffffff9c, &(0x7f0000000040)='./file0\x00', 0x42, 0x0) mmap$IORING_OFF_SQ_RING(&(0x7f0000ffd000/0x3000)=nil, 0x3000, 0x0, 0x12, r4, 0x0) r5 = userfaultfd(0x80801) ioctl$UFFDIO_API(r5, 0xc018aa3f, &(0x7f0000000040)={0xaa, 0x20}) r6 = userfaultfd(0x80801) ioctl$UFFDIO_API(r6, 0xc018aa3f, &(0x7f0000000140)) ioctl$UFFDIO_REGISTER(r6, 0xc020aa00, &(0x7f0000000100)={{&(0x7f0000ffc000/0x4000)=nil, 0x4000}, 0x2}) ioctl$UFFDIO_ZEROPAGE(r5, 0xc020aa04, &(0x7f0000000000)={{&(0x7f0000ffd000/0x1000)=nil, 0x1000}}) r7 = bpf$PROG_LOAD(0x5, &(0x7f0000000140)={0x2, 0x3, &(0x7f0000000200)=ANY=[@ANYBLOB="1800000000120000000000000000000095"], &(0x7f0

Affected

20 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
debianlinux-6.1< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
linuxlinux
linuxlinux>= 2b144498350860b6ee9dc57ff27a93ad488de5dc < c4cb2bfa99513311886c1eb5c1c2ac26f3338a6ec4cb2bfa99513311886c1eb5c1c2ac26f3338a6e
linuxlinux>= 2b144498350860b6ee9dc57ff27a93ad488de5dc < 0b6f19714588cf2366b0364234f97ba963688f630b6f19714588cf2366b0364234f97ba963688f63
linuxlinux>= 2b144498350860b6ee9dc57ff27a93ad488de5dc < 13cca2b73e2b0ec3ea6d6615d615395621d2275213cca2b73e2b0ec3ea6d6615d615395621d22752
linuxlinux>= 2b144498350860b6ee9dc57ff27a93ad488de5dc < 54011fc94422f094eaf47555284de70a4bc32bb954011fc94422f094eaf47555284de70a4bc32bb9
linuxlinux>= 2b144498350860b6ee9dc57ff27a93ad488de5dc < bddf10d26e6e5114e7415a0e442ec6f51a559468bddf10d26e6e5114e7415a0e442ec6f51a559468
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.133-16.1.133-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 0 < 6.8.0-84.846.8.0-84.84
linuxlinux_kernel>= 3.5 < 6.1.1306.1.130
linuxlinux_kernel>= 6.13 < 6.13.66.13.6
linuxlinux_kernel>= 6.2 < 6.6.816.6.81
linuxlinux_kernel>= 6.7 < 6.12.186.12.18
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
vendor_ubuntu5.5MEDIUM
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