ESB-2018.2882 - [Debian] polarssl: Multiple vulnerabilities 2018-09-26

Printable version
PGP/GPG verifiable version

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

===========================================================================
             AUSCERT External Security Bulletin Redistribution

                               ESB-2018.2882
                         polarssl security update
                             26 September 2018

===========================================================================

        AusCERT Security Bulletin Summary
        ---------------------------------

Product:           polarssl
Publisher:         Debian
Operating System:  Debian GNU/Linux 8
Impact/Access:     Access Privileged Data -- Remote/Unauthenticated
                   Denial of Service      -- Remote/Unauthenticated
Resolution:        Patch/Upgrade
CVE Names:         CVE-2018-9989 CVE-2018-9988 CVE-2018-0498
                   CVE-2018-0497 CVE-2013-0169 

Reference:         ASB-2016.0054.2
                   ESB-2018.2775
                   ESB-2014.2485
                   ESB-2014.1820

Original Bulletin: 
   https://lists.debian.org/debian-lts-announce/2018/09/msg00029.html

- --------------------------BEGIN INCLUDED TEXT--------------------

Package        : polarssl
Version        : 1.3.9-2.1+deb8u4
CVE ID         : CVE-2013-0169 CVE-2018-0497 CVE-2018-0498 CVE-2018-9988 
                 CVE-2018-9989
Debian Bug     : 


Two vulnerabilities were discovered in polarssl, a lightweight crypto and
SSL/TLS library (nowadays continued under the name mbedtls) which could
result in plain text recovery via side-channel attacks.

Two other minor vulnerabilities were discovered in polarssl which could
result in arithmetic overflow errors.

CVE-2018-0497

    As a protection against the Lucky Thirteen attack, the TLS code for
    CBC decryption in encrypt-then-MAC mode performs extra MAC
    calculations to compensate for variations in message size due to
    padding. The amount of extra MAC calculation to perform was based on
    the assumption that the bulk of the time is spent in processing
    64-byte blocks, which is correct for most supported hashes but not for
    SHA-384. Correct the amount of extra work for SHA-384 (and SHA-512
    which is currently not used in TLS, and MD2 although no one should
    care about that).

    This is a regression fix for what CVE-2013-0169 had been fixed this.

CVE-2018-0498

    The basis for the Lucky 13 family of attacks is for an attacker to be
    able to distinguish between (long) valid TLS-CBC padding and invalid
    TLS-CBC padding. Since our code sets padlen = 0 for invalid padding,
    the length of the input to the HMAC function gives information about
    that.

    Information about this length (modulo the MD/SHA block size) can be
    deduced from how much MD/SHA padding (this is distinct from TLS-CBC
    padding) is used. If MD/SHA padding is read from a (static) buffer, a
    local attacker could get information about how much is used via a
    cache attack targeting that buffer.

    Let's get rid of this buffer. Now the only buffer used is the
    internal MD/SHA one, which is always read fully by the process()
    function.


CVE-2018-9988

    Prevent arithmetic overflow on bounds check and add bound check
    before signature length read in ssl_parse_server_key_exchange().

CVE-2018-9989

    Prevent arithmetic overflow on bounds check and add bound check
    before length read in ssl_parse_server_psk_hint()


For Debian 8 "Jessie", these problems have been fixed in version
1.3.9-2.1+deb8u4.

We recommend that you upgrade your polarssl packages.

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.

NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

        https://www.auscert.org.au/bulletins/

===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072

Internet Email: auscert@auscert.org.au
Facsimile:      (07) 3365 7031
Telephone:      (07) 3365 4417 (International: +61 7 3365 4417)
                AusCERT personnel answer during Queensland business hours
                which are GMT+10:00 (AEST).
                On call after hours for member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967
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=Yrmz
-----END PGP SIGNATURE-----

« Back to bulletins