CVE-2019-15794
Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs
- Published
- Updated
- Reserved
- Assigned by
- canonical
Description
Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma->vm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow.
Timeline
ID reserved
By canonical
- 8 months later
· 8 months later
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| canonicalCNA (assigner) | 3.1 | High7.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H |
| NVDNVD · Modified | 3.1 | Medium6.7 | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.2% · top 33% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.1.
Weakness
Affected products
- affected 5.3 kernel – < 5.3.0-24.26
- affected 5.0 kernel – < 5.0.0-37.40
References (4)
- https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=270d16ae48a4dbf1c7e25e94cc3e38b4bea37635 (opens in a new tab)x_refsource_MISCx_transferred
- https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=ef81780548d20a786cc77ed4203fca146fd81ce3 (opens in a new tab)x_refsource_MISCx_transferred
- https://usn.ubuntu.com/usn/usn-4208-1 (opens in a new tab)x_refsource_MISCx_transferred
- https://usn.ubuntu.com/usn/usn-4209-1 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2019-15794)Record last updated .