Description
fusermount in FUSE before 2.9.3-15 does not properly clear the environment before invoking (1) mount or (2) umount as root, which allows local users to write to arbitrary files via a crafted LIBMOUNT_MTAB environment variable that is used by mount's debugging feature.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | ntfs-3g | 1:2014.2.15AR.3-3 | — |
| Debian 13 | fuse | 2.9.3-16 | — |
| Debian 13 | ntfs-3g | 1:2014.2.15AR.3-3 | — |
| Debian 12 | fuse | 2.9.3-16 | — |
| Debian 12 | ntfs-3g | 1:2014.2.15AR.3-3 | — |
| Debian 8 | fuse | 2.9.3-15+deb8u1 | DSA-3266-1 |
| Debian 8 | ntfs-3g | 1:2014.2.15AR.2-1+deb8u1 | DSA-3268-2, DSA-3268-1 |
| Debian 7 | fuse | 2.9.0-2+deb7u2 | DSA-3266-1 |
| Debian 7 | ntfs-3g | 1:2012.1.15AR.5-2.1+deb7u1 | DSA-3268-2, DSA-3268-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | fuse | 2.9.2-4ubuntu4.14.04.1 | USN-2617-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 | fuse | 2.9.3-5.1 | SUSE-SU-2015:1053-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 | fuse | 2.9.3-5.1 | SUSE-SU-2015:1053-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | fuse | 2.9.5-1.6 | openSUSE-SU-2024:10378-1 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- Fuse 2.9.3-15 - Local Privilege Escalation EDB-37089 · local · May 23, 2015 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 9
- USN-2617-1 fuse vulnerability Ubuntu Security Notices (USN) · Apr 22, 2026
- DLA-226-1 ntfs-3g - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3266-1 fuse - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-238-1 fuse - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-226-2 ntfs-3g - regression update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3268-2 ntfs-3g - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3268-1 ntfs-3g - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2015:1053-1 Security update for fuse SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10378-1 fuse-2.9.5-1.6 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- DSA-3268 vendor-advisory
- USN-2617-1 vendor-advisory
- FEDORA-2015-8771 vendor-advisory
- FEDORA-2015-8782 vendor-advisory
- FEDORA-2015-8751 vendor-advisory
- 1032386 vdb-entry
- https://gist.github.com/taviso/ecb70eb12d461dd85cba
- 74765 vdb-entry
- FEDORA-2015-8773 vendor-advisory
- openSUSE-SU-2015:1003 vendor-advisory
- DSA-3266 vendor-advisory
- GLSA-201603-04 vendor-advisory
- USN-2617-2 vendor-advisory
- FEDORA-2015-8777 vendor-advisory
- FEDORA-2015-8756 vendor-advisory
- GLSA-201701-19 vendor-advisory
- [oss-security] 20150521 CVE-2015-3202 fuse privilege escalation mailing-list
- openSUSE-SU-2015:0997 vendor-advisory
- http://packetstormsecurity.com/files/132021/Fuse-Local-Privilege-Escalation.html
- https://twitter.com/taviso/status/601370527437967360
- 37089 exploit
- USN-2617-3 vendor-advisory