CVE-2016-6302: Input Validation

Published Aug 23, 2016
·
Updated

An integer underflow flaw leading to a buffer over-read was found in the way OpenSSL parsed TLS session tickets. A remote attacker could use this flaw to crash a TLS server using OpenSSL if it used SHA-512 as HMAC for session tickets.

Other sources

It was found that if a ticket callback changes the HMAC digest to SHA512 the existing sanity checks are not sufficient and an attacker could perform a DoS attack with a malformed ticket.

Upstream patch:

https://github.com/openssl/openssl/commit/1bbe48ab149893a78bf99c8eb8895c928900a16f

— Red Hat

The tlsdecryptticket function in ssl/t1lib.c in OpenSSL before 1.1.0 does not consider the HMAC size during validation of the ticket length, which allows remote attackers to cause a denial of service via a ticket that is too short.

Affected Software

53 affected componentsFixes available
redhat/jbcs-httpd24-apache-commons-daemon<0:1.1.0-1.redhat_2.1.jbcs.el6
0:1.1.0-1.redhat_2.1.jbcs.el6
redhat/jbcs-httpd24-apache-commons-daemon-jsvc<1:1.1.0-1.redhat_2.jbcs.el6
1:1.1.0-1.redhat_2.jbcs.el6
redhat/jbcs-httpd24-apr<0:1.6.3-14.jbcs.el6
0:1.6.3-14.jbcs.el6
redhat/jbcs-httpd24-apr-util<0:1.6.1-9.jbcs.el6
0:1.6.1-9.jbcs.el6
redhat/jbcs-httpd24-httpd<0:2.4.29-17.jbcs.el6
0:2.4.29-17.jbcs.el6
redhat/jbcs-httpd24-nghttp2<0:1.29.0-8.jbcs.el6
0:1.29.0-8.jbcs.el6
redhat/jbcs-httpd24-openssl<1:1.0.2n-11.jbcs.el6
1:1.0.2n-11.jbcs.el6
redhat/jbcs-httpd24-apache-commons-daemon<0:1.1.0-1.redhat_2.1.jbcs.el7
0:1.1.0-1.redhat_2.1.jbcs.el7
redhat/jbcs-httpd24-apache-commons-daemon-jsvc<1:1.1.0-1.redhat_2.jbcs.el7
1:1.1.0-1.redhat_2.jbcs.el7
redhat/jbcs-httpd24-apr<0:1.6.3-14.jbcs.el7
0:1.6.3-14.jbcs.el7
redhat/jbcs-httpd24-apr-util<0:1.6.1-9.jbcs.el7
0:1.6.1-9.jbcs.el7
redhat/jbcs-httpd24-httpd<0:2.4.29-17.jbcs.el7
0:2.4.29-17.jbcs.el7
redhat/jbcs-httpd24-nghttp2<0:1.29.0-8.jbcs.el7
0:1.29.0-8.jbcs.el7
redhat/jbcs-httpd24-openssl<1:1.0.2n-11.jbcs.el7
1:1.0.2n-11.jbcs.el7
redhat/openssl<0:1.0.1e-48.el6_8.3
0:1.0.1e-48.el6_8.3
redhat/openssl<1:1.0.1e-51.el7_2.7
1:1.0.1e-51.el7_2.7
redhat/openssl<1.0.1
1.0.1
redhat/openssl<1.0.2
1.0.2
OpenSSL OpenSSL=1.0.1
OpenSSL OpenSSL=1.0.1a
OpenSSL OpenSSL=1.0.1b
OpenSSL OpenSSL=1.0.1c
OpenSSL OpenSSL=1.0.1d
OpenSSL OpenSSL=1.0.1e
OpenSSL OpenSSL=1.0.1f
OpenSSL OpenSSL=1.0.1g
OpenSSL OpenSSL=1.0.1h
OpenSSL OpenSSL=1.0.1i
OpenSSL OpenSSL=1.0.1j
OpenSSL OpenSSL=1.0.1k
OpenSSL OpenSSL=1.0.1l
OpenSSL OpenSSL=1.0.1m
OpenSSL OpenSSL=1.0.1n
OpenSSL OpenSSL=1.0.1o
OpenSSL OpenSSL=1.0.1p
OpenSSL OpenSSL=1.0.1q
OpenSSL OpenSSL=1.0.1r
OpenSSL OpenSSL=1.0.1s
OpenSSL OpenSSL=1.0.1t
OpenSSL OpenSSL=1.0.2
OpenSSL OpenSSL=1.0.2a
OpenSSL OpenSSL=1.0.2b
OpenSSL OpenSSL=1.0.2c
OpenSSL OpenSSL=1.0.2d
OpenSSL OpenSSL=1.0.2e
OpenSSL OpenSSL=1.0.2f
OpenSSL OpenSSL=1.0.2g
OpenSSL OpenSSL=1.0.2h
ORACLE Linux=6
ORACLE Linux=7
Oracle Solaris=10
Oracle Solaris=11.3
debian/openssl
1.1.1w-0+deb11u11.1.1w-0+deb11u23.0.15-1~deb12u13.0.14-1~deb12u23.5.0-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/jbcs-httpd24-apache-commons-daemon to a version that resolves this vulnerability.

    Fixed in 0:1.1.0-1.redhat_2.1.jbcs.el6
  2. Upgrade

    Upgrade redhat/jbcs-httpd24-apache-commons-daemon-jsvc to a version that resolves this vulnerability.

    Fixed in 1:1.1.0-1.redhat_2.jbcs.el6
  3. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-14.jbcs.el6
  4. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-9.jbcs.el6
  5. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.29-17.jbcs.el6
  6. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.29.0-8.jbcs.el6
  7. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.0.2n-11.jbcs.el6
  8. Upgrade

    Upgrade redhat/jbcs-httpd24-apache-commons-daemon to a version that resolves this vulnerability.

    Fixed in 0:1.1.0-1.redhat_2.1.jbcs.el7
  9. Upgrade

    Upgrade redhat/jbcs-httpd24-apache-commons-daemon-jsvc to a version that resolves this vulnerability.

    Fixed in 1:1.1.0-1.redhat_2.jbcs.el7
  10. Upgrade

    Upgrade redhat/jbcs-httpd24-apr to a version that resolves this vulnerability.

    Fixed in 0:1.6.3-14.jbcs.el7
  11. Upgrade

    Upgrade redhat/jbcs-httpd24-apr-util to a version that resolves this vulnerability.

    Fixed in 0:1.6.1-9.jbcs.el7
  12. Upgrade

    Upgrade redhat/jbcs-httpd24-httpd to a version that resolves this vulnerability.

    Fixed in 0:2.4.29-17.jbcs.el7
  13. Upgrade

    Upgrade redhat/jbcs-httpd24-nghttp2 to a version that resolves this vulnerability.

    Fixed in 0:1.29.0-8.jbcs.el7
  14. Upgrade

    Upgrade redhat/jbcs-httpd24-openssl to a version that resolves this vulnerability.

    Fixed in 1:1.0.2n-11.jbcs.el7
  15. Upgrade

    Upgrade redhat/openssl to a version that resolves this vulnerability.

    Fixed in 0:1.0.1e-48.el6_8.3
  16. Upgrade

    Upgrade redhat/openssl to a version that resolves this vulnerability.

    Fixed in 1:1.0.1e-51.el7_2.7
  17. Upgrade

    Upgrade debian/openssl to a version that resolves this vulnerability.

    Fixed in 1.1.1w-0+deb11u1Fixed in 1.1.1w-0+deb11u2Fixed in 3.0.15-1~deb12u1Fixed in 3.0.14-1~deb12u2Fixed in 3.5.0-1
  18. Upgrade

    Upgrade redhat/openssl to a version that resolves this vulnerability.

    Fixed in 1.0.1
  19. Upgrade

    Upgrade redhat/openssl to a version that resolves this vulnerability.

    Fixed in 1.0.2
  20. Upgrade

    Upgrade OpenSSL to a version that resolves this vulnerability.

    Patch 1bbe48ab149893a78bf99c8eb8895c928900a16f

Event History

Aug 23, 2016
CVE Published
12:00 AM
Aug 24, 2016
Data Sourced
via Red Hat·02:37 PM
DescriptionSeverityAffected Software
Sep 16, 2016
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2016-6302?

CVE-2016-6302 is considered a critical severity vulnerability due to its potential to crash TLS servers.

2

How do I fix CVE-2016-6302?

To fix CVE-2016-6302, you should upgrade to the latest versions of the affected software packages listed in the vulnerability details.

3

What causes CVE-2016-6302?

CVE-2016-6302 is caused by an integer underflow flaw in OpenSSL when parsing TLS session tickets.

4

Is CVE-2016-6302 exploitable over the network?

Yes, CVE-2016-6302 can be exploited remotely, allowing attackers to crash servers using vulnerable versions of OpenSSL.

5

What versions of OpenSSL are affected by CVE-2016-6302?

CVE-2016-6302 affects various versions of OpenSSL, particularly those prior to the patched versions that address this vulnerability.

Company

Resources

Contact

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