fwupd-1.1.4-7.0.1.el8, grub2-2.02-87.0.1.el8, shim-15-15.0.1, shim-unsigned-x64-15-8.0.1.el8
エラータID: AXSA:2020-773:01
以下項目について対処しました。
[Security Fix]
- shim/grub2/fwupdated には、攻撃者が grub2 の欠陥を利用し、
grub の検証プロセスを乗っ取り、改竄し、また Secure Boot の
保護を迂回する脆弱性があります。(CVE-2020-10713)
- shim/grub2/fwupdated には grub のメモリアロケータが要求
された割り当てサイズに対して起こりうる算術オーバフローをチェック
していない問題があります。このことにより、その関数が不正なメモリ
割り当てを返すことで、起動プロセス中に完全性、信頼性、可用性に
影響を与える脆弱性があります。(CVE-2020-14308)
- shim/grub2/fwupdated には UINT32 バイト長の名前の長さを
持つシンボリックリンクを含むsquashfs ファイルシステムを扱う際に
問題があり、この名前のサイズが算術オーバーフローを引き起こし、
攻撃者が操作したデータを用いてヒープベースのバッファオーバーフロー
を引き起こす脆弱性があります。(CVE-2020-14309)
- shim/grub2/fwupdated の read_section_as_string() には
問題があり、最大でUINT32_MAX - 1 の長さのフォント名を期待して
いましたが、フォント値から値を読み出すためにバッファの割り当てを
続行する前に長さを検証していませんでした。攻撃者は UINT32_MAX の
長さを持つ名前の巧妙に細工されたフォントファイルによって、
read_section_as_string() 関数で算術オーバーフロー、ゼロサイズの
割り当てを行い、さらにヒープベースのオーバーフローを引き起こす
脆弱性を引き起こす脆弱性があります。 (CVE-2020-14310)
- shim/grub2/fwupdated には ext ファイルシステム上の
シンボリックリンクの扱いに問題があり、UINT32_MAX の
inode サイズを持つシンボリックリンクを含んだファイルシステム
が算術オーバーフローを引き起こし、ゼロサイズのメモリ割り当てが
起こる脆弱性があります。(CVE-2020-14311)
- shim/grub2/fwupdated には 直接ブートする際に、
kernel の署名の検証に失敗してしまう脆弱性があります。
(CVE-2020-15705)
- shim/grub2/fwupdated には、開放後使用につながる競合条件が存在し、
任意のコードの実行や secure boot の制限の迂回を
引き起こす脆弱性があります。(CVE-2020-15706)
- shim/grub2/fwupdated の sfilinux コンポーネントの
grub_cmd_initrd と grub_initrd_init関数に整数オーバーフロー
が存在し、ヒープベースのバッファオーバーフローを引き起こし、
攻撃者が任意のコードを実行する、UEFI の Secure Boot の
制限を迂回する脆弱性があります。(CVE-2020-15707)
パッケージをアップデートしてください。
A flaw was found in grub2, prior to version 2.06. An attacker may use the GRUB 2 flaw to hijack and tamper the GRUB verification process. This flaw also allows the bypass of Secure Boot protections. In order to load an untrusted or modified kernel, an attacker would first need to establish access to the system such as gaining physical access, obtain the ability to alter a pxe-boot network, or have remote access to a networked system with root access. With this access, an attacker could then craft a string to cause a buffer overflow by injecting a malicious payload that leads to arbitrary code execution within GRUB. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
In grub2 versions before 2.06 the grub memory allocator doesn't check for possible arithmetic overflows on the requested allocation size. This leads the function to return invalid memory allocations which can be further used to cause possible integrity, confidentiality and availability impacts during the boot process.
There's an issue with grub2 in all versions before 2.06 when handling squashfs filesystems containing a symbolic link with name length of UINT32 bytes in size. The name size leads to an arithmetic overflow leading to a zero-size allocation further causing a heap-based buffer overflow with attacker controlled data.
There is an issue on grub2 before version 2.06 at function read_section_as_string(). It expects a font name to be at max UINT32_MAX - 1 length in bytes but it doesn't verify it before proceed with buffer allocation to read the value from the font value. An attacker may leverage that by crafting a malicious font file which has a name with UINT32_MAX, leading to read_section_as_string() to an arithmetic overflow, zero-sized allocation and further heap-based buffer overflow.
There is an issue with grub2 before version 2.06 while handling symlink on ext filesystems. A filesystem containing a symbolic link with an inode size of UINT32_MAX causes an arithmetic overflow leading to a zero-sized memory allocation with subsequent heap-based buffer overflow.
GRUB2 fails to validate kernel signature when booted directly without shim, allowing secure boot to be bypassed. This only affects systems where the kernel signing certificate has been imported directly into the secure boot database and the GRUB image is booted directly without the use of shim. This issue affects GRUB2 version 2.04 and prior versions.
GRUB2 contains a race condition in grub_script_function_create() leading to a use-after-free vulnerability which can be triggered by redefining a function whilst the same function is already executing, leading to arbitrary code execution and secure boot restriction bypass. This issue affects GRUB2 version 2.04 and prior versions.
Integer overflows were discovered in the functions grub_cmd_initrd and grub_initrd_init in the efilinux component of GRUB2, as shipped in Debian, Red Hat, and Ubuntu (the functionality is not included in GRUB2 upstream), leading to a heap-based buffer overflow. These could be triggered by an extremely large number of arguments to the initrd command on 32-bit architectures, or a crafted filesystem with very large files on any architecture. An attacker could use this to execute arbitrary code and bypass UEFI Secure Boot restrictions. This issue affects GRUB2 version 2.04 and prior versions.
N/A
SRPMS
- fwupd-1.1.4-7.0.1.el8.src.rpm
MD5: 92f0cde22d76140b6dd7ab2f6a8d3bd4
SHA-256: be8af99d883bba0caf9cc2d6b35c3c768edd16136af3a062dd4ae1d0a74b0267
Size: 1.29 MB - grub2-2.02-87.0.1.el8.src.rpm
MD5: 32659b7b15f27acf00fbaa609177012c
SHA-256: 3cdd52567b7d729dbcd28ece06c19f52bb0d71f11530f65e70f036d825c189a4
Size: 7.46 MB - shim-15-15.0.1.src.rpm
MD5: fdef091ba4bba85b5c0e94390c114502
SHA-256: 11cbe499417a4c0fb67256783ad7c10ee851b4bedc16461c02fd71a5b93c848b
Size: 767.45 kB - shim-unsigned-x64-15-8.0.1.el8.src.rpm
MD5: 31acf0be009efd5db46a8b61a86b549a
SHA-256: 39a2d744beab9970d8b99045530615954d46dc3da76c466dc6eb3c283edd5dc7
Size: 1.07 MB
Asianux Server 8 for x86_64
- fwupd-1.1.4-7.0.1.el8.x86_64.rpm
MD5: e8f52280e31ea29b2ea5e8e7b10c0e97
SHA-256: 6a1855326b0dca910f607a469840892dfd10b266d45e01fb52d42d788c8e9283
Size: 2.10 MB - grub2-common-2.02-87.0.1.el8.noarch.rpm
MD5: e53541b36c81c900496100ef4f330193
SHA-256: 0ef1a1335bd19e2fda27fba37f0a03f74ad57831eaa5197f3420e2ce399fd1f7
Size: 881.43 kB - grub2-efi-ia32-2.02-87.0.1.el8.x86_64.rpm
MD5: 47b0d967be11bac225d3dd035a900fb8
SHA-256: 7de6614ffa749fbd2dbae37e14adf03f916298de5fff53ece15cd18d97522aa8
Size: 380.54 kB - grub2-efi-ia32-cdboot-2.02-87.0.1.el8.x86_64.rpm
MD5: ad962901566c989e9ef937933246d58a
SHA-256: 4fb52120cb3abeae277e833c20eb14be662ee25e69ea5ac0d5cf2dd2342fc594
Size: 1.14 MB - grub2-efi-ia32-modules-2.02-87.0.1.el8.noarch.rpm
MD5: 4832a3a4da2812c187c52d60174095be
SHA-256: 529a79dd4a1fcf665bd158f58d587bcb63fac90c9ef31b8485c780595d019bf7
Size: 0.97 MB - grub2-efi-x64-2.02-87.0.1.el8.x86_64.rpm
MD5: bc7162e689c9e53c0c7f79dd9d6b940c
SHA-256: de4d9d4f9e0e1038efd7b414c5668e9ac33018ec575ea32fdafa584c576a5202
Size: 402.59 kB - grub2-efi-x64-cdboot-2.02-87.0.1.el8.x86_64.rpm
MD5: 00fa865a92b690c319b5f577e4eac617
SHA-256: fa8960bca287b24ddb3ab3daf6c23b0f13a68404b2b12ff2accbeded2ef86fdb
Size: 1.16 MB - grub2-efi-x64-modules-2.02-87.0.1.el8.noarch.rpm
MD5: 2416ca26364758e2ab0b3989a2f9b52b
SHA-256: a48431f901cfcc0273814e0c447725c368cf39e1fdc054fa9a8e700b63f1fbf4
Size: 1.00 MB - grub2-pc-2.02-87.0.1.el8.x86_64.rpm
MD5: 7a3d3a1a259d85becdfdc28dd1d06cf8
SHA-256: b0db57952fca577da7fcbe150819b1361b26af9ff67dfd27af8323d51dfed031
Size: 36.24 kB - grub2-tools-2.02-87.0.1.el8.x86_64.rpm
MD5: 8ec51c5b6ebd84a76d884b0782bc0451
SHA-256: c4acc9b560320ee737ca413164cea5144d75bc3d271098ddb2512a433e1a03c5
Size: 1.95 MB - grub2-tools-efi-2.02-87.0.1.el8.x86_64.rpm
MD5: e7b17228581b8e1eae0fa4c9aa6dc773
SHA-256: 3ba948fdb7b5d2653c72592ed338243ad762f093c21b5e0a953a7a25c3ddeb6f
Size: 466.12 kB - grub2-tools-extra-2.02-87.0.1.el8.x86_64.rpm
MD5: e71cdec108809f7ea32cea1fc7c65be2
SHA-256: 09a83a170acee136c94bbd45bd48ea679ff58aed68f908b158a147ce5c0c4af0
Size: 1.06 MB - grub2-tools-minimal-2.02-87.0.1.el8.x86_64.rpm
MD5: 40daedc90bee4a90a17da21a77386972
SHA-256: 2a498e19e1432ca102190460d933b613b73e2c2d99cd9e068732380118253591
Size: 201.41 kB - shim-ia32-15-15.0.1.x86_64.rpm
MD5: 400176d5ddfe7c6ea6210b6650466db7
SHA-256: 5fc87ca91543a82040b67c6757a968fddeb77c7b0f4a3c48e069f2047b1adec0
Size: 0.99 MB - shim-x64-15-15.0.1.x86_64.rpm
MD5: eda66924634a28aba36881b0a139ea46
SHA-256: 3e20c7a75f46f4380b49124e47d9c30185a018238867699324a14913bafbd393
Size: 655.59 kB - shim-unsigned-ia32-15-8.0.1.el8.x86_64.rpm
MD5: 5dd6ffe1f220ea2cfe4172173098340c
SHA-256: df586c28733c1221352e2bc603acd623d414c6d2f19c5c440661e8d7d484465d
Size: 463.15 kB - shim-unsigned-x64-15-8.0.1.el8.x86_64.rpm
MD5: 897e27a45dfb7733cb31c5ad8aa1822b
SHA-256: e9bda7116d322111ab3cd602df4c3ebf75afc18e89de6c6e6996ade307afc9ee
Size: 506.54 kB - grub2-pc-modules-2.02-87.0.1.el8.noarch.rpm
MD5: 8a59a910af857af1c0ca321e8ac3686a
SHA-256: 969fcd9e5ba08892563f2499e46064bd1faa8920c805d290f9be7b52f0232187
Size: 861.80 kB