CVE-2019-15791
Reference count underflow in shiftfs
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 5.3.0-22.24, 5.0.0-35.38
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- 1 on Exploit-DB
Summary
In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, shiftfs_btrfs_ioctl_fd_replace() installs an fd referencing a file from the lower filesystem without taking an additional reference to that file. After the btrfs ioctl completes this fd is closed, which then puts a reference to that file, leading to a refcount underflow.
Timeline
- Public exploit on Exploit-DB
EDB-47693
- CVE published
- Record last updated
Affected versions
- Ubuntu Shiftfs in the Linux kernel
From 5.3.0-11.12 · fixed in 5.3.0-22.24; From 5.0 kernel · fixed in 5.0.0-35.38