Description of problem: When transmitting L2TP frames, we derive the outgoing interface's UDP checksum hardware assist capabilities from the tunnel dst dev. This can sometimes be NULL, especially when routing protocols are used and routing changes occur. This patch just checks for NULL dst or dev pointers when checking for netdev hardware assist features. BUG: unable to handle kernel NULL pointer dereference at 0000000c IP: [<f89d074c>] pppol2tpxmit+0x341/0x4da [pppol2tp] pde = 00000000 Oops: 0000 [#1] SMP last sysfs file: /sys/class/net/lo/operstate Modules linked in: pppol2tp pppox pppgeneric slhc ipv6 dummy loop sndhdacodecatihdmi sndhdaintel sndhdacodec snd [...] Code: 8d 45 08 f0 ff 45 08 89 6b 08 c7 43 68 7e fb 9c f8 8a 45 24 83 e0 0c 3c 04 75 09 80 63 64 f3 e9 b4 00 00 00 8b 43 1 EIP: [<f89d074c>] pppol2tpxmit+0x341/0x4da [pppol2tp] SS:ESP 0068:f70a9cac CR2: 000000000000000c
Introduced in ffcebb16 (v2.6.29-rc1~581), fixed in 3feec909 (fixed in v2.6.34-rc2).
Upstream commit: http://git.kernel.org/linus/ffcebb16 http://git.kernel.org/linus/3feec909
Heap-based buffer overflow in the xmlParseAttValueComplex function in parser.c in libxml2 before 2.7.0 allows context-dependent attackers to cause a denial of service (crash) or execute arbitrary code via a long XML entity name.
Buffer overflow in pngpread.c in libpng before 1.2.44 and 1.4.x before 1.4.3, as used in progressive applications, might allow remote attackers to execute arbitrary code via a PNG image that triggers an additional data row.
pam-auth-update for PAM, as used in Ubuntu 8.10 and 9.4, and Debian GNU/Linux, does not properly handle an "empty selection" for system authentication modules in certain rare configurations, which causes any attempt to be successful and allows remote attackers to bypass authentication.
Description of problem: CIFS has the ability to chase MS-DFS referrals. In order to do this it has to be able to resolve hostnames into IP addresses. For this, it uses the keys API to upcall to the cifs.upcall userspace helper. It then resolves the name and hands the address back to the kernel.
The dnsresolver upcall currently used by CIFS is susceptible to cache stuffing. It's possible for a malicious user to stuff the keyring with the results of a lookup, and then trick the server into mounting a server of his choosing.
Tavis Ormandy and Julien Tinnes, Google Security Team reported that Kernels <= 2.6.18.8 are vulnerable to a NULL pointer dereference issue when using MSGMORE on udp sockets.
Fixed upstream already by: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=1e0c14f49d6b393179f423abbac47f85618d3d46
Acknowledgements:
Red Hat would like to thank Tavis Ormandy and Julien Tinnes of the Google Security Team for responsibly reporting this flaw.
Quoting from the upstream commit: Almost all r128's private ioctls require that the CCE state has already been initialised. However, most do not test that this has been done, and will proceed to dereference a null pointer. This may result in a security vulnerability, since some ioctls are unprivileged.
This adds a macro for the common initialisation test and changes all ioctl implementations that require prior initialisation to use that macro.
Also, r128doinitcce() does not test that the CCE state has not been initialised already. Repeated initialisation may lead to a crash or resource leak. This adds that test.
http://git.kernel.org/linus/7dc482dfeeeefcfd000d4271c4626937406756d7
Other references: http://secunia.com/advisories/36707/
The getrandomint function in drivers/char/random.c in the Linux kernel before 2.6.30 produces insufficiently random numbers, which allows attackers to predict the return value, and possibly defeat protection mechanisms based on randomization, via vectors that leverage the function's tendency to "return the same value over and over again for long stretches of time."
Multiple integer overflows in FreeType 2.3.9 and earlier allow remote attackers to execute arbitrary code via vectors related to large values in certain inputs in (1) smooth/ftsmooth.c, (2) sfnt/ttcmap.c, and (3) cff/cffload.c.
Anibal Sacco from Core Security Technologies discovered a NULL pointer dereference flaw in CUPS daemon when handling the IPPTAGUNSUPPORTED, which allows remote attackers with access to CUPS' IPP port to crash cupsd.
Acknowledgements:
Red Hat would like to thank Anibal Sacco from Core Security Technologies for reporting this issue.
Buffer overflow in the SMB1 packet chaining implementation in the chainreply function in process.c in smbd in Samba 3.0.x before 3.3.13 allows remote attackers to cause a denial of service (memory corruption and daemon crash) or possibly execute arbitrary code via a crafted field in a packet.
Common Vulnerabilities and Exposures assigned an identifier CVE-2009-4484 to the following vulnerability:
Buffer overflow in the server in MySQL 5.0.51a on Linux allows remote attackers to execute arbitrary code via crafted data to TCP port 3306, as demonstrated by the vdmysql5 module in VulnDisco Pack Professional 8.11. NOTE: as of 20100106, this disclosure has no actionable information. However, because the VulnDisco Pack author is a reliable researcher, the issue is being assigned a CVE identifier for tracking purposes.
References: http://intevydis.blogspot.com/2010/01/jan-4-2010-mysql-exploit-demo.html http://intevydis.com/vd-list.shtml http://isc.sans.org/diary.html?storyid=7900 http://www.securityfocus.com/bid/37640
More details about the issue may be disclosed in about 2 weeks: http://intevydis.blogspot.com/2010/01/jan-72010-0day-awareness.html
Use-after-free vulnerability in the abstract file-descriptor handling interface in the cupsdDoSelect function in scheduler/select.c in the scheduler in cupsd in CUPS 1.3.7 and 1.3.10 allows remote attackers to cause a denial of service (daemon crash or hang) via a client disconnection during listing of a large number of print jobs, related to improperly maintaining a reference count. NOTE: some of these details are obtained from third party information.
The ACL plugin in Dovecot before 1.1.4 treats negative access rights as if they are positive access rights, which allows attackers to bypass intended access restrictions.
Description of problem: On a 32-bit machine, info.rulecnt >= 0x40000000 leads to integer overflow and the buffer may be smaller than needed. Since ETHTOOLGRXCLSRLALL is unprivileged, this can presumably be used for at least denial of service.
Reference: http://thread.gmane.org/gmane.linux.network/164869
Array index error in the gdthreadevent function in drivers/scsi/gdth.c in the Linux kernel before 2.6.32-rc8 allows local users to cause a denial of service or possibly gain privileges via a negative event index in an IOCTL request.
The connector layer in the Linux kernel before 2.6.31.5 does not require the CAPSYSADMIN capability for certain interaction with the (1) uvesafb, (2) pohmelfs, (3) dst, or (4) dm subsystem, which allows local users to bypass intended access restrictions and gain privileges via calls to functions in these subsystems.
Memory leak in the appletalk subsystem in the Linux kernel 2.4.x through 2.4.37.6 and 2.6.x through 2.6.31, when the appletalk and ipddp modules are loaded but the ipddp"N" device is not found, allows remote attackers to cause a denial of service (memory consumption) via IP-DDP datagrams.
The pollmodeio file for the megaraidsas driver in the Linux kernel 2.6.31.6 and earlier has world-writable permissions, which allows local users to change the I/O mode of the driver by modifying this file.
Multiple race conditions in fs/pipe.c in the Linux kernel before 2.6.32-rc6 allow local users to cause a denial of service (NULL pointer dereference and system crash) or gain privileges by attempting to open an anonymous pipe via a /proc//fd/ pathname.
Robert Swiecki reported an invalid free flaw, that could possibly corrupt the heap, in freetype. This could cause applications linked against freetype to crash (SIGABRT) or, possibly, lead to the execution of arbitrary code if an attacker were able to get a victim to load a malicious font file.
The affected code is not present in Red Hat Enterprise Linux 3 (freetype 2.1.4). In Red Hat Enterprise Linux 4 and 5 this code is present, but does not cause a crash.
This issue has been given the name CVE-2010-2498.
Upstream bug report:
http://savannah.nongnu.org/bugs/index.php?30106
Upstream commit that fixes the issue:
http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=8d22746c9e5af80ff4304aef440986403a5072e2
Acknowledgements:
Red Hat would like to thank Robert Święcki of the Google Security Team for the discovery of this issue.
Buffer overflow in the MacReadPOSTResource function in base/ftobjs.c in FreeType before 2.4.0 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted LaserWriter PS font file with an embedded PFB fragment.
Integer overflow in the grayrenderspan function in smooth/ftgrays.c in FreeType before 2.4.0 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted font file.
Buffer overflow in ftmulti.c in the ftmulti demo program in FreeType before 2.4.2 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted font file.
Multiple buffer overflows in demo programs in FreeType before 2.4.0 allow remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted font file.
Heap-based buffer overflow in the MacReadPOSTResource function in base/ftobjs.c in FreeType before 2.4.0 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted length value in a POST fragment header in a font file.
In his upcoming Blackhat paper and presentation Dan Kaminsky highlights some more issues he has found relating to SSL hash collisions and related vulnerabilities.
His second issue is all about inconsistencies in the interpretation of subject x509 names in certificates. Specifically "issue 2, attack 2c" regarding NULL terminators in a Common Name field. An attacker could create a malicious certificate containing a NULL, which, if they were able to get it signed, could confuse a client into accepting it by mistake.
According to the paper this is said to affect Firefox.
iDefense reported to us a libtiff flaw discovered by Dan Rosenberg. Quoting description from iDefense advisory draft:
Remote exploitation of a stack buffer overflow vulnerability in version 3.9.2 of LibTIFF, as included in various vendors' operating system distributions, could allow an attacker to execute arbitrary code with the privileges of the current user.
...
This vulnerability is due to insufficient bounds checking when copying data into a stack allocated buffer. During the processing of a certain EXIF tag a fixed sized stack buffer is used as a destination location for a memory copy. This memory copy can cause the bounds of a stack buffer to be overflown and this condition may lead to arbitrary code execution.
Quoting upstream PostgreSQL security page: http://www.postgresql.org/support/security.html
If PostgreSQL is configured with LDAP authentication, and your LDAP configuration allows anonymous binds, it is possible for a user to authenticate themselves with an empty password.
Affected versions: 8.3, 8.2
Fixed in versions: 8.3.8, 8.2.14
Severity: A - A vulnerability that is exploitable for privilege escalation without requiring a prior login.
Multiple use-after-free vulnerabilities in libxml2 2.5.10, 2.6.16, 2.6.26, 2.6.27, and 2.6.32, and libxml 1.8.17, allow context-dependent attackers to cause a denial of service (application crash) via crafted (1) Notation or (2) Enumeration attribute types in an XML file, as demonstrated by the Codenomicon XML fuzzing framework.