A flaw was found in the bash functionality that evaluates specially formatted environment variables passed to it from another environment. An attacker could use this feature to override or bypass restrictions to the environment to execute shell commands before restrictions have been applied. Certain services and applications allow remote unauthenticated attackers to provide environment variables, allowing them to exploit this issue.

Acknowledgements:

Red Hat would like to thank Stephane Chazelas for reporting this issue.

GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed function definitions in the values of environment variables, which allows remote attackers to write to files or possibly have unknown other impact via a crafted environment, as demonstrated by vectors involving the ForceCommand feature in OpenSSH sshd, the modcgi and modcgid modules in the Apache HTTP Server, scripts executed by unspecified DHCP clients, and other situations in which setting the environment occurs across a privilege boundary from Bash execution. NOTE: this vulnerability exists because of an incomplete fix for CVE-2014-6271.

A "stack overwrite" vulnerability in GnuPG (gpg) 1.x before 1.4.6, 2.x before 2.0.2, and 1.9.0 through 1.9.95 allows attackers to execute arbitrary code via crafted OpenPGP packets that cause GnuPG to dereference a function pointer from deallocated stack memory.

Xpdf, as used in products such as gpdf, kpdf, pdftohtml, poppler, teTeX, CUPS, libextractor, and others, allows attackers to cause a denial of service (infinite loop) via streams that end prematurely, as demonstrated using the (1) CCITTFaxDecode and (2) DCTDecode streams, aka "Infinite CPU spins."

Integer overflow in Mozilla Thunderbird before 1.5.0.10 and SeaMonkey before 1.0.8 allows remote attackers to trigger a buffer overflow and possibly execute arbitrary code via a text/enhanced or text/richtext e-mail message with an extremely long line.

Format string vulnerability in GnomeMeeting 1.0.2 and earlier allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via format strings in the name, which is not properly handled in a call to the gnomemeetingloginsert function.

Jakob Balle and Carsten Eiram of Secunia Research reported a race condition in NPObjWrapperNewResolve when accessing the properties of a NPObject, a wrapped JSObject. Balle and Eiram demonstrated that this condition could be reached by navigating away from a web page during the loading of a Java applet. Under such conditions the Java object would be destroyed but later called into resulting in a free memory read. An attacker could potentially write to the freed memory before it is reused and run arbitrary code on the victim's computer.

The asn1decodegeneraltime function in lib/krb5/asn.1/asn1decode.c in the ASN.1 GeneralizedTime decoder in MIT Kerberos 5 (aka krb5) before 1.6.4 allows remote attackers to cause a denial of service (daemon crash) or possibly execute arbitrary code via vectors involving an invalid DER encoding that triggers a free of an uninitialized pointer.

gdk-pixbuf through 2.31.1 has GIF loader buffer overflow when initializing decompression tables due to an input validation flaw