CVE-2025-68183: Linux kernel · ima: don't clear IMA_DIGSIG flag when setting or removing non-IMA xattr
Source GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in edd824eb45e4f7e05ad3ab090dab6dbdb79cd292 : patch Linux kernel soon.
Data as of 30 Oct 2026, 16:33 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 7.8 |
|---|
- Patch
- Available – fixed in edd824eb45e4f7e05ad3ab090dab6dbdb79cd292, d2993a7e98eb70c737c6f5365a190e79c72b8407, 88b4cbcf6b041ae0f2fc8a34554a5b6a83a2b7cd +2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: ima: don't clear IMA_DIGSIG flag when setting or removing non-IMA xattr Currently when both IMA and EVM are in fix mode, the IMA signature will be reset to IMA hash if a program first stores IMA signature in security.ima and then writes/removes some other security xattr for the file. For example, on Fedora, after booting the kernel with "ima_appraise=fix evm=fix ima_policy=appraise_tcb" and installing rpm-plugin-ima, installing/reinstalling a package will not make good reference IMA signature generated. Instead IMA hash is generated, # getfattr -m - -d -e hex /usr/bin/bash # file: usr/bin/bash security.ima=0x0404... This happens because when setting security.selinux, the IMA_DIGSIG flag that had been set early was cleared. As a result, IMA hash is generated when the file is closed. Similarly, IMA signature can be cleared on file close after removing security xattr like security.evm or setting/removing ACL. Prevent replacing the IMA file signature with a file hash, by preventing the IMA_DIGSIG flag from being reset. Here's a minimal C reproducer which sets security.selinux as the last step which can also replaced by removing security.evm or setting ACL, #include <stdio.h> #include <sys/xattr.h> #include <fcntl.h> #include <unistd.h> #include <string.h> #include <stdlib.h> int main() { const char* file_path = "/usr/sbin/test_binary"; const char* hex_string = "030204d33204490066306402304"; int length = strlen(hex_string); char* ima_attr_value; int fd; fd = open(file_path, O_WRONLY|O_CREAT|O_EXCL, 0644); if (fd == -1) { perror("Error opening file"); return 1; } ima_attr_value = (char*)malloc(length / 2 ); for (int i = 0, j = 0; i < length; i += 2, j++) { sscanf(hex_string + i, "%2hhx", &ima_attr_value[j]); } if (fsetxattr(fd, "security.ima", ima_attr_value, length/2, 0) == -1) { perror("Error setting extended attribute"); close(fd); return 1; } const char* selinux_value= "system_u:object_r:bin_t:s0"; if (fsetxattr(fd, "security.selinux", selinux_value, strlen(selinux_value), 0) == -1) { perror("Error setting extended attribute"); close(fd); return 1; } close(fd); return 0; }
References
- nvd.nist.gov/vuln/detail/CVE-2025-68183 (opens in a new tab)
- git.kernel.org/stable/c/02aa671c08a4834bef5166743a7b88686fbfa023 (opens in a new tab)
- git.kernel.org/stable/c/7d9ae9d4d45b28c18ca06ae047aabe09d9639643 (opens in a new tab)
- git.kernel.org/stable/c/88b4cbcf6b041ae0f2fc8a34554a5b6a83a2b7cd (opens in a new tab)
- git.kernel.org/stable/c/d2993a7e98eb70c737c6f5365a190e79c72b8407 (opens in a new tab)
- git.kernel.org/stable/c/edd824eb45e4f7e05ad3ab090dab6dbdb79cd292 (opens in a new tab)