Vulnerability Details CVE-2025-39735
In the Linux kernel, the following vulnerability has been resolved:
jfs: fix slab-out-of-bounds read in ea_get()
During the "size_check" label in ea_get(), the code checks if the extended
attribute list (xattr) size matches ea_size. If not, it logs
"ea_get: invalid extended attribute" and calls print_hex_dump().
Here, EALIST_SIZE(ea_buf->xattr) returns 4110417968, which exceeds
INT_MAX (2,147,483,647). Then ea_size is clamped:
int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr));
Although clamp_t aims to bound ea_size between 0 and 4110417968, the upper
limit is treated as an int, causing an overflow above 2^31 - 1. This leads
"size" to wrap around and become negative (-184549328).
The "size" is then passed to print_hex_dump() (called "len" in
print_hex_dump()), it is passed as type size_t (an unsigned
type), this is then stored inside a variable called
"int remaining", which is then assigned to "int linelen" which
is then passed to hex_dump_to_buffer(). In print_hex_dump()
the for loop, iterates through 0 to len-1, where len is
18446744073525002176, calling hex_dump_to_buffer()
on each iteration:
for (i = 0; i < len; i += rowsize) {
linelen = min(remaining, rowsize);
remaining -= rowsize;
hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize,
linebuf, sizeof(linebuf), ascii);
...
}
The expected stopping condition (i < len) is effectively broken
since len is corrupted and very large. This eventually leads to
the "ptr+i" being passed to hex_dump_to_buffer() to get closer
to the end of the actual bounds of "ptr", eventually an out of
bounds access is done in hex_dump_to_buffer() in the following
for loop:
for (j = 0; j < len; j++) {
if (linebuflen < lx + 2)
goto overflow2;
ch = ptr[j];
...
}
To fix this we should validate "EALIST_SIZE(ea_buf->xattr)"
before it is utilised.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.0
EPSS Ranking 1.3%
CVSS Severity
CVSS v3 Score 7.1
Products affected by CVE-2025-39735
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cpe:2.3:o:linux:linux_kernel:4.19.325
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cpe:2.3:o:linux:linux_kernel:5.10.231
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cpe:2.3:o:linux:linux_kernel:5.10.232
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cpe:2.3:o:linux:linux_kernel:5.10.233
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cpe:2.3:o:linux:linux_kernel:5.10.234
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cpe:2.3:o:linux:linux_kernel:5.10.235
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cpe:2.3:o:linux:linux_kernel:5.15.174
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cpe:2.3:o:linux:linux_kernel:5.15.175
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cpe:2.3:o:linux:linux_kernel:5.15.176
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cpe:2.3:o:linux:linux_kernel:5.15.177
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cpe:2.3:o:linux:linux_kernel:5.15.178
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cpe:2.3:o:linux:linux_kernel:5.15.179
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cpe:2.3:o:linux:linux_kernel:5.4.287
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cpe:2.3:o:linux:linux_kernel:5.4.288
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cpe:2.3:o:linux:linux_kernel:5.4.289
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cpe:2.3:o:linux:linux_kernel:5.4.290
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cpe:2.3:o:linux:linux_kernel:5.4.291
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cpe:2.3:o:linux:linux_kernel:6.1.120
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cpe:2.3:o:linux:linux_kernel:6.1.121
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cpe:2.3:o:linux:linux_kernel:6.1.122
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cpe:2.3:o:linux:linux_kernel:6.1.123
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cpe:2.3:o:linux:linux_kernel:6.1.124
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cpe:2.3:o:linux:linux_kernel:6.1.125
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cpe:2.3:o:linux:linux_kernel:6.1.126
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cpe:2.3:o:linux:linux_kernel:6.1.127
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cpe:2.3:o:linux:linux_kernel:6.1.128
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cpe:2.3:o:linux:linux_kernel:6.1.129
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cpe:2.3:o:linux:linux_kernel:6.1.130
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cpe:2.3:o:linux:linux_kernel:6.1.131
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cpe:2.3:o:linux:linux_kernel:6.1.132
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cpe:2.3:o:linux:linux_kernel:6.1.133
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cpe:2.3:o:linux:linux_kernel:6.11.11
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cpe:2.3:o:linux:linux_kernel:6.12.10
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cpe:2.3:o:linux:linux_kernel:6.12.11
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cpe:2.3:o:linux:linux_kernel:6.12.12
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cpe:2.3:o:linux:linux_kernel:6.12.13
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cpe:2.3:o:linux:linux_kernel:6.12.14
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cpe:2.3:o:linux:linux_kernel:6.12.16
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cpe:2.3:o:linux:linux_kernel:6.12.17
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cpe:2.3:o:linux:linux_kernel:6.12.18
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cpe:2.3:o:linux:linux_kernel:6.12.19
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cpe:2.3:o:linux:linux_kernel:6.12.2
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cpe:2.3:o:linux:linux_kernel:6.12.20
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cpe:2.3:o:linux:linux_kernel:6.12.21
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cpe:2.3:o:linux:linux_kernel:6.12.3
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cpe:2.3:o:linux:linux_kernel:6.12.4
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cpe:2.3:o:linux:linux_kernel:6.12.5
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cpe:2.3:o:linux:linux_kernel:6.12.6
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cpe:2.3:o:linux:linux_kernel:6.12.7
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cpe:2.3:o:linux:linux_kernel:6.12.8
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cpe:2.3:o:linux:linux_kernel:6.12.9
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cpe:2.3:o:linux:linux_kernel:6.13
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cpe:2.3:o:linux:linux_kernel:6.13.1
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cpe:2.3:o:linux:linux_kernel:6.13.2
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cpe:2.3:o:linux:linux_kernel:6.13.3
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cpe:2.3:o:linux:linux_kernel:6.13.4
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cpe:2.3:o:linux:linux_kernel:6.13.5
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cpe:2.3:o:linux:linux_kernel:6.13.6
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cpe:2.3:o:linux:linux_kernel:6.13.7
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cpe:2.3:o:linux:linux_kernel:6.13.8
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cpe:2.3:o:linux:linux_kernel:6.13.9
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cpe:2.3:o:linux:linux_kernel:6.14
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cpe:2.3:o:linux:linux_kernel:6.6.64
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cpe:2.3:o:linux:linux_kernel:6.6.65
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cpe:2.3:o:linux:linux_kernel:6.6.66
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cpe:2.3:o:linux:linux_kernel:6.6.67
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cpe:2.3:o:linux:linux_kernel:6.6.68
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cpe:2.3:o:linux:linux_kernel:6.6.69
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cpe:2.3:o:linux:linux_kernel:6.6.70
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cpe:2.3:o:linux:linux_kernel:6.6.71
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cpe:2.3:o:linux:linux_kernel:6.6.72
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cpe:2.3:o:linux:linux_kernel:6.6.73
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cpe:2.3:o:linux:linux_kernel:6.6.74
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cpe:2.3:o:linux:linux_kernel:6.6.75
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cpe:2.3:o:linux:linux_kernel:6.6.76
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cpe:2.3:o:linux:linux_kernel:6.6.77
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cpe:2.3:o:linux:linux_kernel:6.6.78
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cpe:2.3:o:linux:linux_kernel:6.6.79
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cpe:2.3:o:linux:linux_kernel:6.6.80
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cpe:2.3:o:linux:linux_kernel:6.6.81
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cpe:2.3:o:linux:linux_kernel:6.6.83
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cpe:2.3:o:linux:linux_kernel:6.6.84
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cpe:2.3:o:linux:linux_kernel:6.6.85