cbcvebase.
CVE-2025-39917
published 2025-10-01

CVE-2025-39917: In the Linux kernel, the following vulnerability has been resolved: bpf: Fix out-of-bounds dynptr write in bpf_crypto_crypt Stanislav reported that in…

PriorityP341high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.14%
3.8th percentile
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix out-of-bounds dynptr write in bpf_crypto_crypt Stanislav reported that in bpf_crypto_crypt() the destination dynptr's size is not validated to be at least as large as the source dynptr's size before calling into the crypto backend with 'len = src_len'. This can result in an OOB write when the destination is smaller than the source. Concretely, in mentioned function, psrc and pdst are both linear buffers fetched from each dynptr: psrc = __bpf_dynptr_data(src, src_len); [...] pdst = __bpf_dynptr_data_rw(dst, dst_len); [...] err = decrypt ? ctx->type->decrypt(ctx->tfm, psrc, pdst, src_len, piv) : ctx->type->encrypt(ctx->tfm, psrc, pdst, src_len, piv); The crypto backend expects pdst to be large enough with a src_len length that can be written. Add an additional src_len > dst_len check and bail out if it's the case. Note that these kfuncs are accessible under root privileges only.

Affected

10 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.16.8-1 (forky)linux 6.16.8-1 (forky)
linuxlinux
linuxlinux>= 3e1c6f35409f9e447bf37f64840f5b65576bfb78 < 0126358df12d6f476f79251d9c398ac5c1b3062d0126358df12d6f476f79251d9c398ac5c1b3062d
linuxlinux>= 3e1c6f35409f9e447bf37f64840f5b65576bfb78 < c4be24ef0510c146dca4671effb127e97631534bc4be24ef0510c146dca4671effb127e97631534b
linuxlinux>= 3e1c6f35409f9e447bf37f64840f5b65576bfb78 < f9bb6ffa7f5ad0f8ee0f53fc4a10655872ee4a14f9bb6ffa7f5ad0f8ee0f53fc4a10655872ee4a14
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.48-16.12.48-1
linuxlinux_kernel>= 0 < 6.16.8-16.16.8-1
linuxlinux_kernel>= 6.10 < 6.12.486.12.48
linuxlinux_kernel>= 6.13 < 6.16.86.16.8

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8LOW
vendor_redhat7.8HIGH
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