CVE-2026-3842
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
A flaw was found in QEMU allowing a local attacker within a guest virtual machine to write data beyond its allocated memory. This occurs when cpu_physical_memory_map() returns a shorter length than expected, leading to an out-of-bounds write. Successful exploitation could result in unauthorized access to guest memory or corruption of heap-allocated objects.
Risk Assessment
The risk includes potential disclosure of sensitive data, data integrity issues, or denial of service in the virtualization environment. An attacker from the guest can escalate privileges or disrupt other virtual machines.
Recommendation
It is recommended to immediately update QEMU to the latest version containing the fix. Also, restrict access to virtual machine consoles to trusted users only.
Other vulnerabilities in QEMU
See all- CVE-2015-7504High
Heap-based buffer overflow in the pcnet_receive function in hw/net/pcnet.c in QEMU allows guest OS administrators to cause a denial of service (instance crash) or possibly execute arbitrary code via a series of packets in loopback mode.
- CVE-2017-15268High
Qemu through 2.10.0 allows remote attackers to cause a memory leak by triggering slow data-channel read operations, related to io/channel-websock.c.
- CVE-2017-13711High
A use-after-free vulnerability in the sofree function in slirp/socket.c in QEMU allows attackers to cause a denial of service (QEMU instance crash) by failing to properly clear ifq_so from pending packets.
- CVE-2014-0145High
Multiple buffer overflows in QEMU before 1.7.2 and 2.x before 2.0.0 allow local users to cause a denial of service (crash) or possibly execute arbitrary code via a large L1 table in the qcow2_snapshot_load_tmp in the QCOW 2 block driver or various parameters in the DMG block driver.
- CVE-2014-0143High
Multiple integer overflows in QEMU, before version 2.0.0, allow local users to cause a denial of service (crash) by providing crafted input, leading to buffer overflows and memory corruption.
- CVE-2017-10664High
qemu-nbd in QEMU does not ignore SIGPIPE, allowing remote attackers to cause a denial of service (daemon crash) by disconnecting during a server-to-client reply attempt.
- CVE-2017-8309High
A memory leak in audio/audio.c in QEMU allows remote attackers to cause a denial of service by repeatedly starting and stopping audio capture.
- CVE-2017-8284High
The disas_insn function in QEMU before version 2.9.0 does not limit instruction size in TCG mode without hardware acceleration, allowing local users to gain privileges by creating a modified basic block that injects code into a setuid program.
- CVE-2015-8619High
The Human Monitor Interface support in QEMU allows remote attackers to cause a denial of service through out-of-bounds write and application crash.
- CVE-2015-8567High
A memory leak in QEMU's net/vmxnet3.c allows remote attackers to cause a denial of service through excessive memory consumption.
Original NVD description (English source)
A flaw was found in QEMU. This vulnerability allows a local attacker within a guest virtual machine to write data beyond its allocated memory. This occurs when cpu_physical_memory_map() returns a shorter length than expected, leading to an out-of-bounds write. Successful exploitation could result in unauthorized access to guest memory or corruption of heap-allocated objects, potentially causing information disclosure, data integrity issues, or a denial of service.