Loading vulnerability…
CVE-2023-21991 is an easily exploitable vulnerability in the Core component of Oracle VM VirtualBox. Affected versions are Oracle VM VirtualBox prior to 6.1.44 and prior to 7.0.8. Exploitation requires a high-privileged attacker with logon access to the infrastructure where VirtualBox executes. Successful exploitation can compromise Oracle VM VirtualBox and lead to unauthorized read access to a subset of data accessible to VirtualBox. Oracle indicates scope change, meaning exploitation within VirtualBox may significantly affect additional products or components beyond the vulnerable product boundary.
Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.
What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
If you can’t patch tonight, do this now.
Patch, then assume compromise.
1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos.
Repository contains a Linux kernel-module exploit targeting Oracle VirtualBox, with 4 files total: a minimal README, a Makefile for building an out-of-tree kernel module, a large copied VirtualBox header (VMMDev.h) defining HGCM/VMMDev structures and constants, and the main exploit source exp.c. The exploit is not a framework module; exp.c is the primary entry point. The exploit logic is guest-to-host escape oriented. In exp_init(), it maps VGA MMIO at 0xa0000, creates a device/class object, allocates a 32-bit coherent DMA buffer, and repeatedly performs a spray() plus vga_oob_read() loop until it discovers a VBoxC base address. The spray path uses crafted HGCM requests via VMMDevReq_HGCMCall64 and GUEST_PROP_FN_GET_NOTIFICATION, dispatched through the VirtualBox VMMDev I/O port 0xd040. This appears intended to shape host-side heap state and place recognizable patterns for later leakage. After locating the VBoxC base, the exploit enters a second stage using TPM MMIO at 0xfed40000. The tpm_oob_write() routine builds a hardcoded ROP chain using VBoxC-relative gadget offsets and an import-table-relative calculation. The payload is operational rather than generic: it is tuned to execute WinExec-like behavior with the string 'calc', indicating host-side arbitrary code execution on a Windows host process. The chain is delivered bytewise through TPM FIFO registers and triggered with fxrstor64 against TPM_XDATA_FIFO. Overall capability: local privileged guest exploit for VirtualBox escape, combining HGCM heap spraying, VGA out-of-bounds read for information disclosure, and TPM-based out-of-bounds write / control-flow hijack for host code execution. No network communication is present; the relevant endpoints are MMIO bases, I/O ports, kernel build paths, and VirtualBox request/function identifiers.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.
No public activity tracked yet. Mallory keeps watching.
No public activity observed for this vulnerability.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.