CVE-2026-3842: QEMU. This vulnerability
Affects qemuSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 1:8.2.2+ds-0ubuntu1.16 : patch qemu soon.
Data as of 5 Nov 2026, 00:01 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1:8.2.2+ds-0ubuntu1.16, 1:10.1.0+ds-5ubuntu2.6
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 Jul 2026
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 5 Nov 2026.
What to do
Upgrade the Ubuntu qemu to 1:8.2.2+ds-0ubuntu1.16 (package) or 1:10.1.0+ds-5ubuntu2.6 (package).
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10qemupkg:deb/ubuntu/qemu?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.10qemu-hwepkg:deb/ubuntu/qemu-hwe?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSqemupkg:deb/ubuntu/qemu?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSqemu-hwepkg:deb/ubuntu/qemu-hwe?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 25.10qemupkg:deb/ubuntu/qemu?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSqemupkg:deb/ubuntu/qemu?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Apply the official patches provided by Ubuntu in package versions 1:8.2.2+ds-0ubuntu1.16 and 1:10.1.0+ds-5ubuntu2.6 as detailed in Ubuntu Security Notice USN-8161-1. After updating, restart all QEMU virtual machines to ensure the fixes take effect. No additional mitigation steps are indicated by the vendor advisory.
Description
A vulnerability in QEMU allows a local attacker within a guest virtual machine to write data beyond allocated memory due to an out-of-bounds write triggered when cpu_physical_memory_map() returns a shorter length than expected. This can lead to unauthorized access to guest memory, corruption of heap objects, information disclosure, data integrity issues, or denial of service. The flaw affects multiple Ubuntu package versions and has been assigned CVE-2026-3842 with a high severity score of 7.8. Official patches are available in Ubuntu package versions 1:8.2.2+ds-0ubuntu1.16 and 1:10.1.0+ds-5ubuntu2.6. Users are advised to update and restart QEMU virtual machines to apply fixes.