CVE-2016-10027
Smack allows the bypass of TLS protections
Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.
- Record
CVE-2016-10027- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:P/I:N/A:N - Weakness
- CWE-362
- Updated
- 2026-11-02
CVE List No score
Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.
- Record
CVE-2016-10027- Updated
- 2026-11-02
EUVDEUVD-2016-1224 No score
Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.
- Record
EUVD-2016-1224- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-66pq-hqv5-228g
Smack allows the bypass of TLS protections
Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.
- Record
GHSA-66pq-hqv5-228g- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-362
- Updated
- 2026-11-02
OSV
Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.
- Record
CVE-2016-10027- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVGHSA-66pq-hqv5-228g
Smack allows the bypass of TLS protections
Race condition in the XMPP library in Smack before 4.1.9, when the SecurityMode.required TLS setting has been set, allows man-in-the-middle attackers to bypass TLS protections and trigger use of cleartext for client authentication by stripping the "starttls" feature from a server response.
- Record
GHSA-66pq-hqv5-228g- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-362
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
org.igniterealtime.smack:smack-coreMaven |
before 4.1.9 | 4.1.9 |
org.igniterealtime.smack:smack-coreMaven |
before 4.1.9, plus listed versions 4.0.04.0.0-rc14.0.0-rc24.0.14.0.2 Show 27 moreShow less4.0.34.0.44.0.54.0.64.0.74.1.04.1.0-alpha14.1.0-alpha24.1.0-alpha34.1.0-alpha44.1.0-alpha54.1.0-alpha64.1.0-beta14.1.0-beta24.1.0-rc14.1.0-rc24.1.0-rc34.1.0-rc44.1.0-rc54.1.14.1.24.1.34.1.44.1.54.1.64.1.74.1.8 |
4.1.9 |
History
| Recorded | Changed | Sources |
|---|---|---|
| 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-2016-10027 is a medium vulnerability (CVSS 5.9) in Igniterealtime Smack, published January 12, 2017. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.51%, the 74th percentile. Fixed in org.igniterealtime.smack:smack-core 4.1.9.
References
github.com/igniterealtime/Smack/commit/059ee99ba0d5ff7758829acf5a9aeede09ec820b
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/J4WXAZ4JVJXHMEDDXJVWJHPVBF5QCTZF
securityfocus.com/bid/95129
issues.igniterealtime.org/projects/SMACK/issues/SMACK-739
openwall.com/lists/oss-security/2016/12/22/12