cbcvebase.
CVE-2026-46253
published 2026-06-03

CVE-2026-46253: In the Linux kernel, the following vulnerability has been resolved: pstore/ram: fix buffer overflow in persistent_ram_save_old() persistent_ram_save_old() can…

PriorityP344high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.14%
3.5th percentile
In the Linux kernel, the following vulnerability has been resolved: pstore/ram: fix buffer overflow in persistent_ram_save_old() persistent_ram_save_old() can be called multiple times for the same persistent_ram_zone (e.g., via ramoops_pstore_read -> ramoops_get_next_prz for PSTORE_TYPE_DMESG records). Currently, the function only allocates prz->old_log when it is NULL, but it unconditionally updates prz->old_log_size to the current buffer size and then performs memcpy_fromio() using this new size. If the buffer size has grown since the first allocation (which can happen across different kernel boot cycles), this leads to: 1. A heap buffer overflow (OOB write) in the memcpy_fromio() calls 2. A subsequent OOB read when ramoops_pstore_read() accesses the buffer using the incorrect (larger) old_log_size The KASAN splat would look similar to: BUG: KASAN: slab-out-of-bounds in ramoops_pstore_read+0x... Read of size N at addr ... by task ... The conditions are likely extremely hard to hit: 0. Crash with a ramoops write of less-than-record-max-size bytes. 1. Reboot: ramoops registers, pstore_get_records(0) reads old crash, allocates old_log with size X 2. Crash handler registered, timer started (if pstore_update_ms >= 0) 3. Oops happens (non-fatal, system continues) 4. pstore_dump() writes oops via ramoops_pstore_write() size Y (>X) 5. pstore_new_entry = 1, pstore_timer_kick() called 6. System continues running (not a panic oops) 7. Timer fires after pstore_update_ms milliseconds 8. pstore_timefunc() → schedule_work() → pstore_dowork() → pstore_get_records(1) 9. ramoops_get_next_prz() → persistent_ram_save_old() 10. buffer_size() returns Y, but old_log is X bytes 11. Y > X: memcpy_fromio() overflows heap Requirements: - a prior crash record exists that did not fill the record size (almost impossible since the crash handler writes as much as it can possibly fit into the record, capped by max record size and the kmsg buffer almost always exceeds the max record size)

Affected

55 ranges· showing 25
VendorProductVersion rangeFixed in
linuxlinux
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < 58bda5a1d1ee98254383ef34f76b2c35140513ea58bda5a1d1ee98254383ef34f76b2c35140513ea
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < 06d2c8bd108cea503f6f6e13e47495ed1085275f06d2c8bd108cea503f6f6e13e47495ed1085275f
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < 2fa9a047c6a50ec80c3890dd623b85e237f0d1fd2fa9a047c6a50ec80c3890dd623b85e237f0d1fd
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < cff0ef043e16feb5a02307c8f9d0117a96c5587ccff0ef043e16feb5a02307c8f9d0117a96c5587c
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < 9a6fc69a570c0780834246d52c856cc3dbc2605f9a6fc69a570c0780834246d52c856cc3dbc2605f
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < 4f73486ca822305c1cf5b8ebc0b53a6ab3801a814f73486ca822305c1cf5b8ebc0b53a6ab3801a81
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < 7cfe964e61c0ab667abd5f5b68e0acbf783efa4f7cfe964e61c0ab667abd5f5b68e0acbf783efa4f
linuxlinux>= 201e4aca5aa179e6c69a4dcd36a3562e56b8d670 < 5669645c052f235726a85f443769b6fc02f667625669645c052f235726a85f443769b6fc02f66762
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 3.5.1 < 5.10.2525.10.252
linuxlinux_kernel>= 5.11 < 5.15.2025.15.202
linuxlinux_kernel>= 5.16 < 6.1.1656.1.165
linuxlinux_kernel>= 6.13 < 6.18.146.18.14
linuxlinux_kernel>= 6.19 < 6.19.46.19.4
linuxlinux_kernel>= 6.2 < 6.6.1286.6.128
linuxlinux_kernel>= 6.7 < 6.12.756.12.75
ubuntulinux
ubuntulinux-aws
ubuntulinux-aws-5.15

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_ubuntu8.8HIGH
vendor_redhat5.5MEDIUM
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