PT-2026-61110 · Linux · Linux Kernel

CVE-2026-63794 · Published 2026-07-19 · Updated 2026-07-20

Positive Technologies (AI Summary)

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the Linux kernel KVM SVM implementation within the sev dbg crypt() function. In the encryption path handled by sev dbg encrypt user(), the per-iteration transfer length is bounded by the source page offset but not by the destination page offset. When the destination offset is greater than the source offset, the system performs a read-modify-write using a single-page intermediate buffer. This can lead to a buffer overflow where the PSP writes beyond the 4096-byte allocation of the dst tpage buffer, and subsequent memory copy operations overflow by up to 15 bytes.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-63794

Affected Products

Linux Kernel

References · 10

• https://nvd.nist.gov/vuln/detail/CVE-2026-63794 · Security Note
• https://git.kernel.org/stable/c/64f2449841ffc7d203183aa4c748c9c77951ecc5 · Note
• https://git.kernel.org/stable/c/e1a0fe288dee07b7da25a71e007c1ecd1080315b · Note
• https://git.kernel.org/stable/c/720949ed666f34ff28ffdfe1471a5861d1e41fdf · Note
• https://git.kernel.org/stable/c/889c2a9c59897ca912bf39df5bb92555a0a13df4 · Note
• https://git.kernel.org/stable/c/9349b50f4b11f135fe73b56cb2c2c872d8bc71d7 · Note
• https://git.kernel.org/stable/c/2753a097d1fe24c4351c608048612c74108aa89f · Note
• https://twitter.com/windowsforum/status/2079130991797457037 · Twitter Post
• https://git.kernel.org/stable/c/78ee2d50185a037b3d2452a97f3dad69c3f7f389 · Note
• https://git.kernel.org/stable/c/f701ae476cb92a3a3d8844bb39bb63b4512684c8 · Note