kernel: a bug in ip_frag_reasm() can cause a crash in ip_do_fragment()

A security flaw was found in the ip_frag_reasm() function in net/ipv4/ip_fragment.c in the Linux kernel from 4.19-rc1 to 4.19-rc3 inclusive, which can cause a later system crash in ip_do_fragment(). With certain non-default, but non-rare, configuration of a victim host, an attacker can trigger this crash remotely, thus leading to a remote denial-of-service.

kernel: stack-based buffer overflow in chap_server_compute_md5() in iscsi target

A security flaw was found in the chap_server_compute_md5() function in the ISCSI target code in the Linux kernel in a way an authentication request from an ISCSI initiator is processed. An unauthenticated remote attacker can cause a stack buffer overflow and smash up to 17 bytes of the stack. The attack requires the iSCSI target to be enabled on the victim host. Depending on how the target's code was built (i.e. depending on a compiler, compile flags and hardware architecture) an attack may lead to a system crash and thus to a denial-of-service or possibly to a non-authorized access to data exported by an iSCSI target. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although we believe it is highly unlikely. Kernel versions 4.18.x, 4.14.x and 3.10.x are believed to be vulnerable.

kernel: use-after-free Read in vhost_transport_send_pkt

A flaw was found in the Linux Kernel where an attacker may be able to have an uncontrolled read to kernel-memory from within a vm guest. A race condition between connect() and close() function may allow an attacker using the AF_VSOCK protocol to gather a 4 byte information leak or possibly intercept or corrupt AF_VSOCK messages destined to other clients.

kernel: crash (possible privesc) in kernel crypto api.

A flaw was found in the crypto subsystem of the Linux kernel before version kernel-4.15-rc4. The "null skcipher" was being dropped when each af_alg_ctx was freed instead of when the aead_tfm was freed. This can cause the null skcipher to be freed while it is still in use leading to a local user being able to crash the system or possibly escalate privileges.

kernel: NULL pointer dereference in fs/hfsplus/dir.c:hfsplus_lookup() when operating on a file in a crafted hfs+ image

An issue was discovered in the Linux kernel through 4.17.10. There is a NULL pointer dereference and panic in hfsplus_lookup() in fs/hfsplus/dir.c when opening a file (that is purportedly a hard link) in an hfs+ filesystem that has malformed catalog data, and is mounted read-only without a metadata directory.

kernel: NULL pointer dereference in fs/crypto/crypto.c:fscrypt_do_page_crypto() when operating on a corrupted f2fs image

An issue was discovered in the Linux kernel through 4.17.10. There is a NULL pointer dereference in fscrypt_do_page_crypto() in fs/crypto/crypto.c when operating on a file in a corrupted f2fs image.

kernel: Buffer overflow in fs/f2fs/inline.c:truncate_inline_inode() when unmounting a crafted f2fs image

An issue was discovered in the Linux kernel through 4.17.10. There is a buffer overflow in truncate_inline_inode() in fs/f2fs/inline.c when umounting an f2fs image, because a length value may be negative.

kernel: Out-of-bounds access in fs/f2fs/segment.c:__remove_dirty_segment() when mounting a crafted f2fs image

An issue was discovered in the Linux kernel through 4.17.10. There is an out-of-bounds access in __remove_dirty_segment() in fs/f2fs/segment.c when mounting an f2fs image.

kernel: Invalid pointer dereference in io_ctl_map_page() when mounting and operating a crafted btrfs image

An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in io_ctl_map_page() when mounting and operating a crafted btrfs image, because of a lack of block group item validation in check_leaf_item in fs/btrfs/tree-checker.c.

kernel: Invalid pointer dereference in btrfs_root_node() when mounting a crafted btrfs image

An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in btrfs_root_node() when mounting a crafted btrfs image, because of a lack of chunk block group mapping validation in btrfs_read_block_groups in fs/btrfs/extent-tree.c, and a lack of empty-tree checks in check_leaf in fs/btrfs/tree-checker.c.

kernel: Use-after-free in try_merge_free_space() when mounting crafted btrfs image

An issue was discovered in the Linux kernel through 4.17.10. There is a use-after-free in try_merge_free_space() when mounting a crafted btrfs image, because of a lack of chunk type flag checks in btrfs_check_chunk_valid in fs/btrfs/volumes.c.

kernel: Out-of-bounds access in write_extent_buffer() when mounting and operating a crafted btrfs image

An issue was discovered in the Linux kernel through 4.17.10. There is out-of-bounds access in write_extent_buffer() when mounting and operating a crafted btrfs image, because of a lack of verification that each block group has a corresponding chunk at mount time, within btrfs_read_block_groups in fs/btrfs/extent-tree.c.

kernel: Invalid pointer dereference in fs/btrfs/relocation.c:__del_reloc_root() when mounting crafted btrfs image

An issue was discovered in the Linux kernel through 4.17.10. There is an invalid pointer dereference in __del_reloc_root() in fs/btrfs/relocation.c when mounting a crafted btrfs image, related to removing reloc rb_trees when reloc control has not been initialized.

kernel: Integer overflow in drivers/video/fbdev/uvesafb.c:uvesafb_setcmap() allows for potential denial of service

An integer overflow in the uvesafb_setcmap function in drivers/video/fbdev/uvesafb.c in the Linux kernel before 4.17.4 could result in local attackers being able to crash the kernel or potentially elevate privileges because kmalloc_array is not used.

kernel: Missing check in fs/inode.c:inode_init_owner() does not clear SGID bit on non-directories for non-members

The inode_init_owner function in fs/inode.c in the Linux kernel through 3.16 allows local users to create files with an unintended group ownership, in a scenario where a directory is SGID to a certain group and is writable by a user who is not a member of that group. Here, the non-member can trigger creation of a plain file whose group ownership is that group. The intended behavior was that the non-member can trigger creation of a directory (but not a plain file) whose group ownership is that group. The non-member can escalate privileges by making the plain file executable and SGID.

Druide Antidote through 9.5.1 on Windows and Linux allows remote code execution through the update mechanism by leveraging use of HTTP to download installation packages.

kernel: divide-by-zero in fs/f2fs/super.c

An issue was discovered in fs/f2fs/super.c in the Linux kernel through 4.17.3, which does not properly validate secs_per_zone in a corrupted f2fs image, as demonstrated by a divide-by-zero error.

kernel: out-of-bounds memory access in fs/f2fs/inline.c

An issue was discovered in fs/f2fs/inline.c in the Linux kernel through 4.4. A denial of service (out-of-bounds memory access and BUG) can occur for a modified f2fs filesystem image in which an inline inode contains an invalid reserved blkaddr.

kernel: slab out-of-bounds read in fs/f2fs/inode.c

An issue was discovered in fs/f2fs/inode.c in the Linux kernel through 4.17.3. A denial of service (slab out-of-bounds read and BUG) can occur for a modified f2fs filesystem image in which FI_EXTRA_ATTR is set in an inode.

kernel: divide-by-zero in fs/f2fs/super.c

An issue was discovered in fs/f2fs/super.c in the Linux kernel through 4.17.3. There is an out-of-bounds read or a divide-by-zero error for an incorrect user_block_count in a corrupted f2fs image, leading to a denial of service (BUG).