CVE-2018-15858
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp...
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
- Record
CVE-2018-15858- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 2.1 Low
AV:L/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-476
- Updated
- 2026-11-02
CVE List No score
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
- Record
CVE-2018-15858- Updated
- 2026-11-02
EUVDEUVD-2018-7715 No score
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
- Record
EUVD-2018-7715- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-4rvw-gf8w-hj4x
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp...
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
- Record
GHSA-4rvw-gf8w-hj4x- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
OSV
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
- Record
CVE-2018-15858- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2018-15858
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
- Record
DEBIAN-CVE-2018-15858- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Show 6 moreShow less
OSVUBUNTU-CVE-2018-15858
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.
- Record
UBUNTU-CVE-2018-15858- CVSS 3.0
- 5.5 Medium
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVMGASA-2018-0369 No score
Updated libxkbcommon packages fix security vulnerabilities
Updated libxkbcommon packages fix security vulnerabilities:
Endless recursion exists in xkbcomp/expr.c in xkbcommon and libxkbcommon before 0.8.1, which could be used by local attackers to crash xkbcommon users by supplying a crafted keymap file that triggers boolean negation (CVE-2018-15853).
Unchecked NULL pointer usage in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because geometry tokens were desupported incorrectly (CVE-2018-15854).
Unchecked NULL pointer usage in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because the XkbFile for an xkb_geometry section was mishandled (CVE-2018-15855).
An infinite loop when reaching EOL unexpectedly in compose/parser.c (aka the keymap parser) in xkbcommon before 0.8.1 could be used by local attackers to cause a denial of service during parsing of crafted keymap files (CVE-2018-15856).
An invalid free in ExprAppendMultiKeysymList in xkbcomp/ast-build.c in xkbcommon before 0.8.1 could be used by local attackers to crash xkbcommon keymap parsers or possibly have unspecified other impact by supplying a crafted keymap file (CVE-2018-15857).
Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file (CVE-2018-15858).
Unchecked NULL pointer usage when parsing invalid atoms in ExprResolveLhs in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because lookup failures are mishandled (CVE-2018-15859).
Unchecked NULL pointer usage in ExprResolveLhs in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file that triggers an xkb_intern_atom failure (CVE-2018-15861).
Unchecked NULL pointer usage in LookupModMask in xkbcomp/expr.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file with invalid virtual modifiers (CVE-2018-15862).
Unchecked NULL pointer usage in ResolveStateAndPredicate in xkbcomp/compat.c in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file with a no-op modmask expression (CVE-2018-15863).
Unchecked NULL pointer usage in resolve_keysym in xkbcomp/parser.y in xkbcommon before 0.8.2 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because a map access attempt can occur for a map that was never created (CVE-2018-15864).
- Record
MGASA-2018-0369- Updated
- 2026-11-02
OSVSUSE-SU-2018:3685-1 No score
Security update for libxkbcommon
This update for libxkbcommon to version 0.8.2 fixes the following issues:
- Fix a few NULL-dereferences, out-of-bounds access and undefined behavior in the XKB text format parser.
- CVE-2018-15853: Endless recursion could have been used by local attackers to crash xkbcommon users by supplying a crafted keymap file that triggers boolean negation (bsc#1105832).
- CVE-2018-15854: Unchecked NULL pointer usage could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because geometry tokens were desupported incorrectly (bsc#1105832).
- CVE-2018-15855: Unchecked NULL pointer usage could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because the XkbFile for an xkb_geometry section was mishandled (bsc#1105832).
- CVE-2018-15856: An infinite loop when reaching EOL unexpectedly could be used by local attackers to cause a denial of service during parsing of crafted keymap files (bsc#1105832).
- CVE-2018-15857: An invalid free in ExprAppendMultiKeysymList could have been used by local attackers to crash xkbcommon keymap parsers or possibly have unspecified other impact by supplying a crafted keymap file (bsc#1105832).
- CVE-2018-15858: Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file (bsc#1105832).
- CVE-2018-15859: Unchecked NULL pointer usage when parsing invalid atoms in ExprResolveLhs could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because lookup failures are mishandled (bsc#1105832).
- CVE-2018-15861: Unchecked NULL pointer usage in ExprResolveLhs could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file that triggers an xkb_intern_atom failure (bsc#1105832).
- CVE-2018-15862: Unchecked NULL pointer usage in LookupModMask could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file with invalid virtual modifiers (bsc#1105832).
- CVE-2018-15863: Unchecked NULL pointer usage in ResolveStateAndPredicate could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file with a no-op modmask expression (bsc#1105832).
- CVE-2018-15864: Unchecked NULL pointer usage in resolve_keysym could have been used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file, because a map access attempt can occur for a map that was never created (bsc#1105832).
- Record
SUSE-SU-2018:3685-1- Updated
- 2026-11-02
OSVSUSE-SU-2024:0037-1 No score
Security update for libxkbcommon
This update for libxkbcommon fixes the following issues:
Fixed multiple memory handling and correctness issues (bsc#1105832):
- CVE-2018-15859
- CVE-2018-15856
- CVE-2018-15858
- CVE-2018-15864
- CVE-2018-15863
- CVE-2018-15862
- CVE-2018-15861
- CVE-2018-15855
- CVE-2018-15854
- CVE-2018-15857
- CVE-2018-15853
- Record
SUSE-SU-2024:0037-1- Updated
- 2026-11-02
OSVUSN-3786-1 No score
libxkbcommon vulnerabilities
It was discovered that libxkbcommon incorrectly handled certain files. An attacker could possibly use this issue to cause a denial of service. (CVE-2018-15853, CVE-2018-15854, CVE-2018-15855, CVE-2018-15856, CVE-2018-15857, CVE-2018-15858, CVE-2018-15859, CVE-2018-15861, CVE-2018-15862, CVE-2018-15863, CVE-2018-15864)
- Record
USN-3786-1- Updated
- 2026-11-02
OSVUSN-3786-2 No score
libxkbcommon vulnerabilities
USN-3786-1 fixed several vulnerabilities in libxkbcommon. This update provides the corresponding update for Ubuntu 18.04 LTS.
Original advisory details:
It was discovered that libxkbcommon incorrectly handled certain files. An attacker could possibly use this issue to cause a denial of service. (CVE-2018-15853, CVE-2018-15854, CVE-2018-15855, CVE-2018-15856, CVE-2018-15857, CVE-2018-15858, CVE-2018-15859, CVE-2018-15861, CVE-2018-15862, CVE-2018-15863, CVE-2018-15864)
- Record
USN-3786-2- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
libxkbcommonDebian:12 |
before 0.8.2-1 | 0.8.2-1 |
libxkbcommonDebian:13 |
before 0.8.2-1 | 0.8.2-1 |
libxkbcommonDebian:14 |
before 0.8.2-1 | 0.8.2-1 |
libxkbcommonMageia:6 From an advisory covering 11 CVEs |
before 0.8.2-1.mga6 | 0.8.2-1.mga6 |
libxkbcommonSUSE:Linux Enterprise Module for Basesystem 15 From an advisory covering 11 CVEs |
before 0.8.2-3.3.1 | 0.8.2-3.3.1 |
libxkbcommonSUSE:Linux Enterprise Software Development Kit 12 SP5 From an advisory covering 11 CVEs |
before 0.6.1-9.3.1 | 0.6.1-9.3.1 |
libxkbcommonSUSE:Linux Enterprise Server 12 SP5 From an advisory covering 11 CVEs |
before 0.6.1-9.3.1 | 0.6.1-9.3.1 |
libxkbcommonSUSE:Linux Enterprise Server for SAP Applications 12 SP5 From an advisory covering 11 CVEs |
before 0.6.1-9.3.1 | 0.6.1-9.3.1 |
libxkbcommonUbuntu:16.04:LTS |
before 0.5.0-1ubuntu2.1, plus listed versions 0.5.0-1ubuntu2 |
0.5.0-1ubuntu2.1 |
libxkbcommonUbuntu:18.04:LTS |
before 0.8.0-1ubuntu0.1, plus listed versions 0.7.1-20.8.0-1 |
0.8.0-1ubuntu0.1 |
libxkbcommonUbuntu:14.04:LTS From an advisory covering 11 CVEs |
before 0.4.1-0ubuntu1.1, plus listed versions 0.3.1-10.3.1-20.4.1-0ubuntu1 |
0.4.1-0ubuntu1.1 |
libxkbcommonUbuntu:16.04:LTS From an advisory covering 11 CVEs |
before 0.5.0-1ubuntu2.1, plus listed versions 0.5.0-1ubuntu2 |
0.5.0-1ubuntu2.1 |
libxkbcommonUbuntu:18.04:LTS From an advisory covering 11 CVEs |
before 0.8.0-1ubuntu0.1, plus listed versions 0.7.1-20.8.0-1 |
0.8.0-1ubuntu0.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-15858 is a medium vulnerability (CVSS 5.5) in Xkbcommon, published August 25, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 37th percentile. Fixed in libxkbcommon 0.8.2-1.
References
github.com/xkbcommon/libxkbcommon/commit/badb428e63387140720f22486b3acbd3d738859f
security.gentoo.org/glsa/201810-05
usn.ubuntu.com/3786-1
lists.freedesktop.org/archives/wayland-devel/2018-August/039232.html
nvd.nist.gov/vuln/detail/CVE-2018-15858
Show 33 moreShow less
security-tracker.debian.org/tracker/CVE-2018-15858
advisories.mageia.org/MGASA-2018-0369.html
bugs.mageia.org/show_bug.cgi?id=23506
lists.fedoraproject.org/archives/list/[email protected]/thread/377JCLG64STYRNYZZ4B5QKGX2MAW6JUX
suse.com/support/update/announcement/2018/suse-su-20183685-1
bugzilla.suse.com/1105832
ubuntu.com/security/CVE-2018-15858
cve.org/CVERecord?id=CVE-2018-15858