From: Xiangyu Chen <xiangyu.c...@windriver.com> There an out-of-bounds read at fs/ntfs.c, a physically present attacker may leverage that by presenting a specially crafted NTFS file system image to read arbitrary memory locations. A successful attack may allow sensitive data cached in memory or EFI variables values to be leaked presenting a high Confidentiality risk.
Signed-off-by: Xiangyu Chen <xiangyu.c...@windriver.com> Signed-off-by: Steve Sakoman <st...@sakoman.com> --- .../grub/files/CVE-2023-4693.patch | 63 +++++++++++++++++++ meta/recipes-bsp/grub/grub2.inc | 1 + 2 files changed, 64 insertions(+) create mode 100644 meta/recipes-bsp/grub/files/CVE-2023-4693.patch diff --git a/meta/recipes-bsp/grub/files/CVE-2023-4693.patch b/meta/recipes-bsp/grub/files/CVE-2023-4693.patch new file mode 100644 index 0000000000..544226a9aa --- /dev/null +++ b/meta/recipes-bsp/grub/files/CVE-2023-4693.patch @@ -0,0 +1,63 @@ +From 0ed2458cc4eff6d9a9199527e2a0b6d445802f94 Mon Sep 17 00:00:00 2001 +From: Maxim Suhanov <dfirb...@gmail.com> +Date: Mon, 28 Aug 2023 16:32:33 +0300 +Subject: fs/ntfs: Fix an OOB read when reading data from the resident $DATA + attribute + +When reading a file containing resident data, i.e., the file data is stored in +the $DATA attribute within the NTFS file record, not in external clusters, +there are no checks that this resident data actually fits the corresponding +file record segment. + +When parsing a specially-crafted file system image, the current NTFS code will +read the file data from an arbitrary, attacker-chosen memory offset and of +arbitrary, attacker-chosen length. + +This allows an attacker to display arbitrary chunks of memory, which could +contain sensitive information like password hashes or even plain-text, +obfuscated passwords from BS EFI variables. + +This fix implements a check to ensure that resident data is read from the +corresponding file record segment only. + +Fixes: CVE-2023-4693 + +Upstream-Status: Backport from +[https://git.savannah.gnu.org/cgit/grub.git/commit/?id=0ed2458cc4eff6d9a9199527e2a0b6d445802f94] +CVE: CVE-2023-4693 + +Reported-by: Maxim Suhanov <dfirb...@gmail.com> +Signed-off-by: Maxim Suhanov <dfirb...@gmail.com> +Reviewed-by: Daniel Kiper <daniel.ki...@oracle.com> +Signed-off-by: Xiangyu Chen <xiangyu.c...@windriver.com> +--- + grub-core/fs/ntfs.c | 13 ++++++++++++- + 1 file changed, 12 insertions(+), 1 deletion(-) + +diff --git a/grub-core/fs/ntfs.c b/grub-core/fs/ntfs.c +index c3c4db1..a68e173 100644 +--- a/grub-core/fs/ntfs.c ++++ b/grub-core/fs/ntfs.c +@@ -401,7 +401,18 @@ read_data (struct grub_ntfs_attr *at, grub_uint8_t *pa, grub_uint8_t *dest, + { + if (ofs + len > u32at (pa, 0x10)) + return grub_error (GRUB_ERR_BAD_FS, "read out of range"); +- grub_memcpy (dest, pa + u32at (pa, 0x14) + ofs, len); ++ ++ if (u32at (pa, 0x10) > (at->mft->data->mft_size << GRUB_NTFS_BLK_SHR)) ++ return grub_error (GRUB_ERR_BAD_FS, "resident attribute too large"); ++ ++ if (pa >= at->mft->buf + (at->mft->data->mft_size << GRUB_NTFS_BLK_SHR)) ++ return grub_error (GRUB_ERR_BAD_FS, "resident attribute out of range"); ++ ++ if (u16at (pa, 0x14) + u32at (pa, 0x10) > ++ (grub_addr_t) at->mft->buf + (at->mft->data->mft_size << GRUB_NTFS_BLK_SHR) - (grub_addr_t) pa) ++ return grub_error (GRUB_ERR_BAD_FS, "resident attribute out of range"); ++ ++ grub_memcpy (dest, pa + u16at (pa, 0x14) + ofs, len); + return 0; + } + +-- +cgit v1.1 + diff --git a/meta/recipes-bsp/grub/grub2.inc b/meta/recipes-bsp/grub/grub2.inc index ac73a0b940..fa949fc081 100644 --- a/meta/recipes-bsp/grub/grub2.inc +++ b/meta/recipes-bsp/grub/grub2.inc @@ -43,6 +43,7 @@ SRC_URI = "${GNU_MIRROR}/grub/grub-${PV}.tar.gz \ file://0001-risc-v-Handle-R_RISCV_CALL_PLT-reloc.patch \ file://0001-fs-ext2-Ignore-checksum-seed-incompat-feature.patch \ file://CVE-2023-4692.patch \ + file://CVE-2023-4693.patch \ " SRC_URI[sha256sum] = "23b64b4c741569f9426ed2e3d0e6780796fca081bee4c99f62aa3f53ae803f5f" -- 2.34.1
-=-=-=-=-=-=-=-=-=-=-=- Links: You receive all messages sent to this group. View/Reply Online (#189854): https://lists.openembedded.org/g/openembedded-core/message/189854 Mute This Topic: https://lists.openembedded.org/mt/102299565/21656 Group Owner: openembedded-core+ow...@lists.openembedded.org Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-