Security readout for executives and security teams
Plain-English summary
This is a local Ubuntu kernel vulnerability in shiftfs. A user with access to the affected system could trigger a kernel type confusion bug, causing a crash or possibly changing kernel-controlled data. The source bundle does not show remote exploitation or confirmed active attacks.
Executive priority
Treat as high priority for affected Ubuntu fleets, especially multi-user systems. The issue requires local access, so urgency is below remotely exploitable kernel bugs, but kernel integrity and availability impact justify prompt patching.
Technical view
The flaw is in Ubuntu’s non-upstream shiftfs patch for Linux 5.0 and 5.3 kernels. shiftfs_btrfs_ioctl_fd_replace() obtains a file pointer with fdget(oldfd), then shiftfs_real_fdget() casts file->private_data to struct shiftfs_file_info without validating the underlying filesystem-specific type.
Likely exposure
Exposure is limited to Ubuntu systems running affected 5.0 or 5.3 kernel series with shiftfs present. Attackers need local privileges. Non-Ubuntu upstream kernels and Ubuntu systems outside the cited affected kernel series are not shown as affected in the provided sources.
Exploitation context
The CVSS vector indicates local access, low complexity, low privileges, and no user interaction. The bundle says denial of service or possible arbitrary code execution. CISA KEV is false, and no cited source confirms active exploitation.
Researcher notes
The core issue is CWE-843 type confusion around file->private_data. Because the field is filesystem-dependent, unsafe casting can corrupt kernel behavior. The source bundle supports denial of service and possible code execution, but does not establish exploit reliability or public weaponization.
Mitigation direction
- Apply Ubuntu kernel security updates referenced in USN-4183-1 and USN-4184-1.
- Reboot affected systems into the updated kernel after patching.
- Check Ubuntu guidance if an affected kernel cannot be replaced immediately.
- Prioritize shared systems where untrusted local users can run code.
Validation and detection
- Inventory Ubuntu hosts running 5.0 or 5.3 kernel series.
- Compare installed kernel package versions with Ubuntu USN-4183-1 and USN-4184-1.
- Confirm the running kernel changed after reboot, not only the installed package.
- Record whether local users or workloads can access affected systems.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-843: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2019-15792 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H1.85.2Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.1HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://usn.ubuntu.com/usn/usn-4183-1CVE reference · x_refsource_MISC
- https://usn.ubuntu.com/usn/usn-4184-1CVE reference · x_refsource_MISC
- https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=5df147c8140efc71ac0879ae3b0057f577226d4cCVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Access of Resource Using Incompatible Type ('Type Confusion')
Access of Resource Using Incompatible Type ('Type Confusion') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.