概要
Linux/Unix 主機上安裝的一個或多個套件存有弱點,供應商表示將不會修補。
說明
Linux/Unix 主機上安裝了一個或多個受到弱點影響的套件,且供應商未提供可用的修補程式。
- 在 Linux 核心中,已解決下列弱點: mm/mremap: fix address wraparound in move_page_tables() On 32-bit platforms, it is possible for the expression `len + old_addr < old_end` to be false-positive if `len + old_addr` wraps around. `old_addr` is the cursor in the old range up to which page table entries have been moved; so if the operation succeeded, `old_addr` is the *end* of the old region, and adding `len` to it can wrap. The overflow causes mremap() to mistakenly believe that PTEs have been copied; the consequence is that mremap() bails out, but doesn't move the PTEs back before the new VMA is unmapped, causing anonymous pages in the region to be lost. So basically if userspace tries to mremap() a private-anon region and hits this bug, mremap() will return an error and the private-anon region's contents appear to have been zeroed. The idea of this check is that `old_end - len` is the original start address, and writing the check that way also makes it easier to read; so fix the check by rearranging the comparison accordingly. (An alternate fix would be to refactor this function by introducing an orig_old_start variable or such.) Tested in a VM with a 32-bit X86 kernel; without the patch: ``` user@horn:~/big_mremap$ cat test.c #define _GNU_SOURCE #include <stdlib.h> #include <stdio.h> #include <err.h> #include <sys/mman.h> #define ADDR1 ((void*)0x60000000) #define ADDR2 ((void*)0x10000000) #define SIZE 0x50000000uL int main(void) { unsigned char *p1 = mmap(ADDR1, SIZE, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED_NOREPLACE, -1, 0); if (p1 == MAP_FAILED) err(1, mmap 1); unsigned char *p2 = mmap(ADDR2, SIZE, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE|MAP_FIXED_NOREPLACE, -1, 0); if (p2 == MAP_FAILED) err(1, mmap 2); *p1 = 0x41; printf(first char is 0x%02hhx\n, *p1); unsigned char *p3 = mremap(p1, SIZE, SIZE, MREMAP_MAYMOVE|MREMAP_FIXED, p2); if (p3 == MAP_FAILED) { printf(mremap() failed;
first char is 0x%02hhx\n, *p1); } else { printf(mremap() succeeded; first char is 0x%02hhx\n, *p3); } } user@horn:~/big_mremap$ gcc -static -o test test.c user@horn:~/big_mremap$ setarch -R ./test first char is 0x41 mremap() failed; first char is 0x00 ``` With the patch: ``` user@horn:~/big_mremap$ setarch -R ./test first char is 0x41 mremap() succeeded; first char is 0x41 ``` (CVE-2024-53111)
請注意,Nessus 依賴供應商報告的套件存在。
Plugin 詳細資訊
檔案名稱: unpatched_CVE_2024_53111.nasl
代理程式: unix
支援的感應器: Nessus Agent, Nessus
風險資訊
媒介: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C
媒介: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
時間媒介: CVSS:3.0/E:U/RL:O/RC:C
弱點資訊
必要的 KB 項目: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched
可輕鬆利用: No known exploits are available