Paper/Archive/CVE-2026-68156

CVE-2026-68156

Linux Linux — libceph: refresh auth->authorizer_buf{,_len} after authorizer update

Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: libceph: refresh auth->authorizer_buf{,_len} after authorizer update ceph_x_create_authorizer() caches au->buf->vec.iov_base and au->buf->vec.iov_len in struct ceph_auth_handshake. These cached values are then used by the messenger connect code when sending the authorizer. ceph_x_update_authorizer() can rebuild the authorizer when a newer service ticket is available. If the rebuilt authorizer no longer fits in the existing buffer, ceph_x_build_authorizer() drops its reference to au->buf and allocates a new one. If this is the final reference, ceph_buffer_put() frees the old ceph_buffer and its vec.iov_base, but auth->authorizer_buf still points at that freed memory. A subsequent msgr1 reconnect can therefore queue the stale pointer and trigger a KASAN slab-use-after-free in _copy_from_iter() while tcp_sendmsg() copies the authorizer. Refresh auth->authorizer_buf and auth->authorizer_buf_len after a successful authorizer rebuild so the messenger sends the current buffer.

Affected

ProductAffectedFixed inSource
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 2334e9997308305ee4fd508fdfe6086c4150ed602334e9997308305ee4fd508fdfe6086c4150ed60CNA
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 79a273df64238a4ade8b709689a78589f755b8ef79a273df64238a4ade8b709689a78589f755b8efCNA
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 26f814187abceee90dbb29a02133adb4786fbb1326f814187abceee90dbb29a02133adb4786fbb13CNA
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 9d37aec9ffe4e743dabc3f84502e9723e17a30d49d37aec9ffe4e743dabc3f84502e9723e17a30d4CNA
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 75e82e8944ac1efe9fdb88bd2f14d9a031282bdf75e82e8944ac1efe9fdb88bd2f14d9a031282bdfCNA
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 0060ec912292a550198d8d18ac95b433c92a70910060ec912292a550198d8d18ac95b433c92a7091CNA
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 5ecfcd5c05866f185357700b81b461dae4f5ebb25ecfcd5c05866f185357700b81b461dae4f5ebb2CNA
Linux0bed9b5c523d577378b6f83eab5835fe30c27208 – < 937d61f86d377a3aa578adae7a3dfcecdddf9d89937d61f86d377a3aa578adae7a3dfcecdddf9d89CNA
Linux29c65a277a64645af853e8c9a9b3dda0ddc421e0–CNA
Linuxd2c7223497cf8228416c70e3f4238ddd6c5bdf3c–CNA
Linux3.4.50 – < 3.53.5CNA
Linux3.9.7 – < 3.103.10CNA

Scores by source

Linux (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgit.kernel.org/stable/c/2334e9997308305ee4fd508fdfe6086c4150ed60refgit.kernel.org/stable/c/79a273df64238a4ade8b709689a78589f755b8efrefgit.kernel.org/stable/c/26f814187abceee90dbb29a02133adb4786fbb13refgit.kernel.org/stable/c/9d37aec9ffe4e743dabc3f84502e9723e17a30d4refgit.kernel.org/stable/c/75e82e8944ac1efe9fdb88bd2f14d9a031282bdfrefgit.kernel.org/stable/c/0060ec912292a550198d8d18ac95b433c92a7091refgit.kernel.org/stable/c/5ecfcd5c05866f185357700b81b461dae4f5ebb2refgit.kernel.org/stable/c/937d61f86d377a3aa578adae7a3dfcecdddf9d89