CVE-2018-16868
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls...
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
Attack profile
How easy it is to exploit
- Attack vector
- Physical
- Complexity
- High
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
- Record
CVE-2018-16868- CVSS 3.0
- 4.7 Medium
CVSS:3.0/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N - Weakness
- CWE-203
- Updated
- 2026-11-02
EUVDEUVD-2018-8659
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
- Record
EUVD-2018-8659- CVSS 3.0
- 4.7 Medium
CVSS:3.0/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-qjx3-4wr5-3c93
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls...
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
- Record
GHSA-qjx3-4wr5-3c93- CVSS 3.1
- 5.6 Medium
CVSS:3.1/AV:P/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N - Weakness
- CWE-203
- Updated
- 2026-11-02
NVD
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
- Record
CVE-2018-16868- CVSS 3.1
- 5.6 Medium
CVSS:3.1/AV:P/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N - CVSS 3.0
- 4.7 Medium
CVSS:3.0/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N - CVSS 2.0
- 3.3 Low
AV:L/AC:M/Au:N/C:P/I:P/A:N - Weakness
- CWE-203
- Updated
- 2026-11-02
OSV
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
- Record
CVE-2018-16868- CVSS 3.1
- 5.6 Medium
CVSS:3.1/AV:P/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2018-16868
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
- Record
DEBIAN-CVE-2018-16868- CVSS 3.1
- 5.6 Medium
CVSS:3.1/AV:P/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N - Updated
- 2026-11-02
Show 7 moreShow less
OSVUBUNTU-CVE-2018-16868
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.
- Record
UBUNTU-CVE-2018-16868- CVSS 3.1
- 5.6 Medium
CVSS:3.1/AV:P/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N - CVSS 3.0
- 4.7 Medium
CVSS:3.0/AV:P/AC:H/PR:H/UI:N/S:C/C:H/I:N/A:N - CVSS 3.0
- 5.6 Medium
CVSS:3.0/AV:P/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N - Updated
- 2026-11-02
OSVMGASA-2019-0103 No score
Updated gnutls packages fix security vulnerability
A Bleichenbacher type side-channel based padding oracle attack was found in the way gnutls handles verification of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run process on the same physical core as the victim process, could use this to extract plaintext or in some cases downgrade any TLS connections to a vulnerable server. (CVE-2018-16868)
- Record
MGASA-2019-0103- Updated
- 2026-11-02
OSVopenSUSE-SU-2019:1353-1 No score
Security update for gnutls
This update for gnutls fixes to version 3.6.7 the following issues:
Security issued fixed:
- CVE-2019-3836: Fixed an invalid pointer access via malformed TLS1.3 async messages (bsc#1130682).
- CVE-2019-3829: Fixed a double free vulnerability in the certificate verification API (bsc#1130681).
- CVE-2018-16868: Fixed Bleichenbacher-like side channel leakage in PKCS#1 v1.5 verification and padding oracle verification (bsc#1118087)
Non-security issue fixed:
- Update gnutls to support TLS 1.3 (fate#327114)
This update was imported from the SUSE:SLE-15:Update update project.
- Record
openSUSE-SU-2019:1353-1- Updated
- 2026-11-02
OSVopenSUSE-SU-2019:1477-1 No score
Security update for gnutls
This update for gnutls fixes the following issues:
Security issue fixed:
- CVE-2018-16868: Fixed Bleichenbacher-like side channel leakage in PKCS#1 v1.5 verification (bsc#1118087).
Non-security issue fixed:
- Explicitly require libnettle 3.4.1 to prevent missing symbol errors (bsc#1134856).
This update was imported from the SUSE:SLE-15:Update update project.
- Record
openSUSE-SU-2019:1477-1- Updated
- 2026-11-02
OSVSUSE-SU-2019:1121-1 No score
Security update for gnutls
This update for gnutls fixes to version 3.6.7 the following issues:
Security issued fixed:
- CVE-2019-3836: Fixed an invalid pointer access via malformed TLS1.3 async messages (bsc#1130682).
- CVE-2019-3829: Fixed a double free vulnerability in the certificate verification API (bsc#1130681).
- CVE-2018-16868: Fixed Bleichenbacher-like side channel leakage in PKCS#1 v1.5 verification and padding oracle verification (bsc#1118087)
Non-security issue fixed:
- Update gnutls to support TLS 1.3 (fate#327114)
- Record
SUSE-SU-2019:1121-1- Updated
- 2026-11-02
OSVSUSE-SU-2019:1351-1 No score
Security update for gnutls
This update for gnutls fixes the following issues:
Security issue fixed:
- CVE-2018-16868: Fixed Bleichenbacher-like side channel leakage in PKCS#1 v1.5 verification (bsc#1118087).
Non-security issue fixed:
- Explicitly require libnettle 3.4.1 to prevent missing symbol errors (bsc#1134856).
- Record
SUSE-SU-2019:1351-1- Updated
- 2026-11-02
OSVSUSE-SU-2019:1351-2 No score
Security update for gnutls
This update for gnutls fixes the following issues:
Security issue fixed:
- CVE-2018-16868: Fixed Bleichenbacher-like side channel leakage in PKCS#1 v1.5 verification (bsc#1118087).
Non-security issue fixed:
- Explicitly require libnettle 3.4.1 to prevent missing symbol errors (bsc#1134856).
- Record
SUSE-SU-2019:1351-2- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
gnutls28Debian:12 |
before 3.6.5-2 | 3.6.5-2 |
gnutls28Debian:13 |
before 3.6.5-2 | 3.6.5-2 |
gnutls28Debian:14 |
before 3.6.5-2 | 3.6.5-2 |
gnutlsMageia:6 |
before 3.5.13-1.2.mga6 | 3.5.13-1.2.mga6 |
gnutlsSUSE:Linux Enterprise Module for Basesystem 15 From an advisory covering 3 CVEs |
before 3.6.7-6.8.1 | 3.6.7-6.8.1 |
gnutlsSUSE:Linux Enterprise Module for Desktop Applications 15 From an advisory covering 3 CVEs |
before 3.6.7-6.8.1 | 3.6.7-6.8.1 |
gnutlsSUSE:Linux Enterprise Module for Basesystem 15 |
before 3.6.7-6.11.1 | 3.6.7-6.11.1 |
gnutlsSUSE:Linux Enterprise Module for Desktop Applications 15 |
before 3.6.7-6.11.1 | 3.6.7-6.11.1 |
gnutlsSUSE:Linux Enterprise Module for Basesystem 15 SP1 |
before 3.6.7-6.11.1 | 3.6.7-6.11.1 |
gnutls26Ubuntu:Pro:14.04:LTS |
All versions, plus listed versions 2.12.23-1ubuntu42.12.23-1ubuntu52.12.23-12ubuntu12.12.23-12ubuntu22.12.23-12ubuntu2.1 Show 8 moreShow less2.12.23-12ubuntu2.22.12.23-12ubuntu2.32.12.23-12ubuntu2.42.12.23-12ubuntu2.52.12.23-12ubuntu2.62.12.23-12ubuntu2.72.12.23-12ubuntu2.82.12.23-12ubuntu2.10+esm1 |
None known |
Show 5 moreShow less
| Package | Affected | Fixed |
|---|---|---|
gnutls28Ubuntu:Pro:16.04:LTS |
All versions, plus listed versions 3.3.15-5ubuntu23.3.18-1ubuntu13.3.20-1ubuntu13.4.9-2ubuntu13.4.10-4ubuntu1 Show 13 moreShow less3.4.10-4ubuntu1.13.4.10-4ubuntu1.23.4.10-4ubuntu1.33.4.10-4ubuntu1.43.4.10-4ubuntu1.53.4.10-4ubuntu1.63.4.10-4ubuntu1.73.4.10-4ubuntu1.83.4.10-4ubuntu1.93.4.10-4ubuntu1.9+esm13.4.10-4ubuntu1.9+esm23.4.10-4ubuntu1.9+esm33.4.10-4ubuntu1.9+esm4 |
None known |
gnutls28Ubuntu:Pro:18.04:LTS |
All versions, plus listed versions 3.5.8-6ubuntu33.5.17-1ubuntu13.5.17-1ubuntu33.5.18-1ubuntu13.5.18-1ubuntu1.1 Show 9 moreShow less3.5.18-1ubuntu1.23.5.18-1ubuntu1.33.5.18-1ubuntu1.43.5.18-1ubuntu1.53.5.18-1ubuntu1.63.5.18-1ubuntu1.6+esm13.5.18-1ubuntu1.6+esm23.5.18-1ubuntu1.6+esm33.5.18-1ubuntu1.6+esm4 |
None known |
gnutlsopenSUSE:Leap 15.0 From an advisory covering 3 CVEs |
before 3.6.7-lp150.9.1 | 3.6.7-lp150.9.1 |
gnutlsopenSUSE:Leap 15.0 |
before 3.6.7-lp151.2.3.1 | 3.6.7-lp151.2.3.1 |
gnutlsopenSUSE:Leap 15.1 |
before 3.6.7-lp151.2.3.1 | 3.6.7-lp151.2.3.1 |
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-2018-16868 is a medium vulnerability (CVSS 4.7) in [unknown] Gnutls, published December 3, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.58%, the 47th percentile. Fixed in gnutls28 3.6.5-2.
References
securityfocus.com/bid/106080
lists.opensuse.org/opensuse-security-announce/2019-05/msg00017.html
cat.eyalro.net
bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16868
nvd.nist.gov/vuln/detail/CVE-2018-16868
Show 19 moreShow less
github.com/advisories/GHSA-qjx3-4wr5-3c93
security-tracker.debian.org/tracker/CVE-2018-16868
advisories.mageia.org/MGASA-2019-0103.html
bugs.mageia.org/show_bug.cgi?id=24066
lists.fedoraproject.org/archives/list/[email protected]/thread/INZ7O52ANE3RPKUWDI3TKPVVHQNKHVKY
suse.com/support/update/announcement/2019/suse-su-20191121-1
bugzilla.suse.com/1118087
ubuntu.com/security/CVE-2018-16868
cve.org/CVERecord?id=CVE-2018-16868