In util-linux before 2.32-rc1, bash-completion/umount allows local users to gain privileges by embedding shell commands in a mountpoint name
In util-linux before 2.32-rc1, bash-completion/umount allows local users to gain privileges by embedding shell commands in a mountpoint name, which is mishandled during a umount command (within Bash) by a different user, as demonstrated by logging in as root and entering umount followed by a tab character for autocompletion.
- Published
- Mar 6, 2018
- Updated
- Jun 16, 2026
- EPSS
- 0.4% · 36th percentile
- CWE
- —
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Report tools
Action score
31
Monitor
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.4%
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| kernel | util-linux | cpe:2.3:a:kernel:util-linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- kernel util-linuxup to 2.31 inclusive
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | bash-completion | all versions | — |
| Debian:12 | util-linux | before 2.31.1-0.5 | 2.31.1-0.5 |
| Debian:9 | util-linux | before 2.29.2-1+deb9u1 | 2.29.2-1+deb9u1 |
| openSUSE:Leap 15.4 | python-libmount | before 2.31.1-150000.9.24.1 | 2.31.1-150000.9.24.1 |
| SUSE:Linux Enterprise Desktop 12 SP3 | python-libmount | before 2.29.2-3.8.1 | 2.29.2-3.8.1 |
| SUSE:Linux Enterprise Desktop 12 SP3 | python-libmount | before 2.29.2-3.12.1 | 2.29.2-3.12.1 |
| SUSE:Linux Enterprise Desktop 12 SP3 | util-linux | before 2.29.2-3.8.1 | 2.29.2-3.8.1 |
| SUSE:Linux Enterprise Desktop 12 SP3 | util-linux | before 2.29.2-3.12.1 | 2.29.2-3.12.1 |
| SUSE:Linux Enterprise Desktop 12 SP3 | util-linux-systemd | before 2.29.2-3.12.1 | 2.29.2-3.12.1 |
| SUSE:Linux Enterprise Desktop 12 SP3 | util-linux-systemd | before 2.29.2-3.8.1 | 2.29.2-3.8.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | util-linux | before 2.33.2-150100.4.40.1 | 2.33.2-150100.4.40.1 |
| SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS | util-linux-systemd | before 2.33.2-150100.4.40.1 | 2.33.2-150100.4.40.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 | util-linux | before 2.31.1-9.3.1 | 2.31.1-9.3.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 | util-linux-systemd | before 2.31.1-9.3.1 | 2.31.1-9.3.1 |
| SUSE:Linux Enterprise Server 12 SP5 | python-libmount | before 2.33.2-4.33.1 | 2.33.2-4.33.1 |
| SUSE:Linux Enterprise Server 12 SP5 | util-linux-systemd | before 2.33.2-4.33.1 | 2.33.2-4.33.1 |
| SUSE:Linux Enterprise Software Development Kit 12 SP5 | util-linux | before 2.33.2-4.33.1 | 2.33.2-4.33.1 |
| SUSE:OpenStack Cloud 7 | python-libmount | before 2.28-44.18.38 | 2.28-44.18.38 |
| SUSE:OpenStack Cloud 7 | util-linux | before 2.28-44.18.18 | 2.28-44.18.18 |
| SUSE:OpenStack Cloud 7 | util-linux-systemd | before 2.28-44.18.25 | 2.28-44.18.25 |
Same product
kernel: all recordsOther highest-scoring records for the same primary product.
- CVE-2015-5224The mkostemp function in login-utils in util-linux when used incorrectly allows remote attackers to cause file name collision and possibly o40Plan
- CVE-2016-2779runuser in util-linux allows local users to escape to the parent session via a crafted TIOCSTI ioctl call, which pushes characters to the te31Monitor
- CVE-2007-5191mount and umount in util-linux and loop-aes-utils call the setuid and setgid functions in the wrong order and do not check the return values28Monitor
- CVE-2020-21583An issue was discovered in hwclock.13-v2.27 allows attackers to gain escalated privlidges or execute arbitrary commands via the path paramet26Monitor
- CVE-2021-3996A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem.22Monitor
- CVE-2021-3995A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem.22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:util-linux | 2.31.1-0.5 · Debian:12 | Package registry (OSV) |
| opensuse:python-libmount | 2.31.1-150000.9.24.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| suse:python-libmount | 2.29.2-3.8.1 · SUSE:Linux Enterprise Desktop 12 SP3 | Package registry (OSV) |
| suse:util-linux | 2.31.1-9.3.1 · SUSE:Linux Enterprise Module for Basesystem 15 | Package registry (OSV) |
| suse:util-linux-systemd | 2.31.1-9.3.1 · SUSE:Linux Enterprise Module for Basesystem 15 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
—
CVSS vector
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- www.securityfocus.com/bid/103367
- bugs.debian.org/892179
- github.com/karelzak/util-linux/commit/75f03badd7ed9f1dd951863d75e756883d3acc55
- github.com/karelzak/util-linux/issues/539
- usn.ubuntu.com/4512-1/
- www.debian.org/security/2018/dsa-4134
- security.netapp.com/advisory/ntap-20241213-0002/
Vendor advisories and official records. Exploit/PoC links are deliberately left out.