Description
In glibc 2.26 and earlier there is confusion in the usage of getcwd() by realpath() which can be used to write before the destination buffer leading to a buffer underflow and potential code execution.
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 | glibc | 2.26-4 | — |
| Debian 13 | glibc | 2.26-4 | — |
| Debian 12 | glibc | 2.26-4 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | glibc | 2.23-0ubuntu10 | USN-3534-1 |
| Ubuntu 14.04 LTS | eglibc | 2.19-0ubuntu6.14 | USN-3534-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 16.04 LTS | musl | 1.1.9-1ubuntu0.1~esm2 | USN-4768-1 |
| Ubuntu Pro 14.04 LTS | musl | 0.9.15-1ubuntu0.1~esm1 | USN-4768-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | nscd +7 | 2.17-222.el7 | RHSA-2018:0805 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | glibc | 2.22-62.3.4 | SUSE-SU-2018:0451-1, SUSE-SU-2018:0074-1 |
| SLES 12 SP2 | glibc | 2.22-62.3.4 | SUSE-SU-2018:0451-1, SUSE-SU-2018:0074-1 |
| SLES 12 SP1 | glibc | 2.19-40.9.5 | SUSE-SU-2018:0071-1 |
| SLES 12 | glibc | 2.19-22.24.5 | SUSE-SU-2018:2187-1, SUSE-SU-2018:0076-1 |
| SLES 11 SP4 | glibc | 2.11.3-17.110.3.1 | SUSE-SU-2018:0565-1, SUSE-SU-2018:0075-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 11 SP3 | glibc | 2.11.3-17.110.3.1 | SUSE-SU-2018:0565-1, SUSE-SU-2018:0075-1 |
| SLES for SAP 12 SP3 | glibc | 2.22-62.3.4 | SUSE-SU-2018:0451-1, SUSE-SU-2018:0074-1 |
| SLES for SAP 12 SP2 | glibc | 2.22-62.3.4 | SUSE-SU-2018:0451-1, SUSE-SU-2018:0074-1 |
| SLES for SAP 12 SP1 | glibc | 2.19-40.9.5 | SUSE-SU-2018:0071-1 |
| SLES for SAP 11 SP4 | glibc | 2.11.3-17.110.3.1 | SUSE-SU-2018:0565-1, SUSE-SU-2018:0075-1 |
| SUSE OpenStack Cloud 6 | glibc | 2.19-40.9.5 | SUSE-SU-2018:0071-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | glibc | 2.11.3-17.110.3.1 | SUSE-SU-2018:0565-1, SUSE-SU-2018:0075-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | glibc | 2.34-1.2 | openSUSE-SU-2024:10792-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | nscd +6 | 2.17-222.el7 | ELSA-2018-0805 |
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.
Metasploit 1 module
-
glibc 'realpath()' Privilege Escalation
exploit/linux/local/glibc_realpath_priv_esc
Exploit-DB 2
- glibc - 'realpath()' Privilege Escalation (Metasploit) EDB-44889 · local · Jun 13, 2018 · verified
- glibc < 2.26 - 'getcwd()' Local Privilege Escalation EDB-43775 · local · Jan 16, 2018 · verified
GitHub 2 repositories
-
0x00-0x00/CVE-2018-1000001 ★ 31 · Feb 7, 2018
glibc getcwd() local privilege escalation compiled binaries
-
usernameid0/tools-for-CVE-2018-1000001 ★ 0 · Mar 1, 2022
Tools for get offsets and adding patch for support i386
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 12
- USN-4768-1 musl vulnerabilities Ubuntu Security Notices (USN) · Jun 29, 2026
- RHSA-2018:0805 Red Hat Security Advisory: glibc security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- USN-3534-1 eglibc, glibc vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- SUSE-SU-2018:0075-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10792-1 glibc-2.34-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:0451-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:2187-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:0071-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:0565-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:0074-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:0076-1 Security update for glibc SUSE / openSUSE Security Updates · Feb 4, 2026
- ELSA-2018-0805 Moderate: glibc security, bug fix, and enhancement update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Apr 16, 2018
References
- [oss-security] 20180111 Libc Realpath Buffer Underflow CVE-2018-1000001 mailing-list
- USN-3534-1 vendor-advisory
- https://www.halfdog.net/Security/2017/LibcRealpathBufferUnderflow/
- 102525 vdb-entry
- 44889 exploit
- 43775 exploit
- USN-3536-1 vendor-advisory
- RHSA-2018:0805 vendor-advisory
- 1040162 vdb-entry
- https://security.netapp.com/advisory/ntap-20190404-0003/