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.
Dan Kaminsky pointed out that using partial MD4 and using that to generate a sequence number, of which only 24-bits are truly unguessable, seriously undermine the goals of random sequence number generation.
In particular, with only 24-bits being truly unguessable, packet injection into a session using even something like brute force is a real potential possibility.
We only use 24-bits because we regenerate the random number every 5 minutes "just in case." But what does is trade a "we don't know" kind of theoretical issue for a provably real one (brute force attack).
Therefore [Dave Miller] moving us more in line with RFC1948 (as well as OpenBSD and Solaris), to use MD5 and a full 32-bit result in the generated sequence number.
MD5 was selected as a compromise between performance loss and theoretical ability to be compromised. Willy Tarreau did extensive testing and SHA1 was found to harm performance too much to be considered seriously at this time.
We may later add a sysctl for various modes (ie. a "super secure" mode that uses SHA1 if people want that, and an "insecure" mode that doesn't use cryptographic hashing at all for people in protected environments where that might be safe to do).
[Dave Miller] also moved the sequence number generators out of random.c (they never really belonged there, and are only there due to historical artifacts), and fixed a bug in DCCP sequence number generation (on ipv6 the 43-bit sequence number was truncated to 32-bits).
Acknowledgements:
Red Hat would like to thank Dan Kaminsky for reporting this issue.
F5 BIG-IP appliances 9.x before 9.4.8-HF5, 10.x before 10.2.4, 11.0.x before 11.0.0-HF2, and 11.1.x before 11.1.0-HF3, and Enterprise Manager before 2.1.0-HF2, 2.2.x before 2.2.0-HF1, and 2.3.x before 2.3.0-HF3, use a single SSH private key across different customers' installations and do not properly restrict access to this key, which makes it easier for remote attackers to perform SSH logins via the PubkeyAuthentication option.
Unspecified vulnerability in the MySQL Server component in Oracle MySQL 5.1.64 and earlier, and 5.5.26 and earlier, allows remote authenticated users to affect confidentiality, integrity, and availability via unknown vectors related to Information Schema.
Multiple XML External Entity (XXE) vulnerabilities in the Configuration utility in F5 BIG-IP LTM, ASM, GTM, and Link Controller 11.0 through 11.6.0 and 10.0.0 through 10.2.4, AAM 11.4.0 through 11.6.0, ARM 11.3.0 through 11.6.0, Analytics 11.0.0 through 11.6.0, APM and Edge Gateway 11.0.0 through 11.6.0 and 10.1.0 through 10.2.4, PEM 11.3.0 through 11.6.0, PSM 11.0.0 through 11.4.1 and 10.0.0 through 10.2.4, and WOM 11.0.0 through 11.3.0 and 10.0.0 through 10.2.4 and Enterprise Manager 3.0.0 through 3.1.1 and 2.1.0 through 2.3.0 allow remote authenticated users to read arbitrary files and cause a denial of service via a crafted request, as demonstrated using (1) viewList or (2) deal elements.
Buffer overflow in the mcpq daemon in F5 BIG-IP systems 10.x before 10.2.4 HF12, 11.x before 11.2.1 HF15, 11.3.x, 11.4.x before 11.4.1 HF9, 11.5.x before 11.5.2 HF1, and 11.6.0 before HF4, and Enterprise Manager 2.1.0 through 2.3.0 and 3.x before 3.1.1 HF5 allows remote authenticated administrators to cause a denial of service via unspecified vectors.
Cross-site scripting (XSS) vulnerability in tmui/dashboard/echo.jsp in the Configuration utility in F5 BIG-IP LTM, APM, ASM, GTM, and Link Controller 11.0.0 before 11.6.0 and 10.1.0 through 10.2.4, AAM 11.4.0 before 11.6.0, AFM and PEM 11.3.0 before 11.6.0, Analytics 11.0.0 through 11.5.1, Edge Gateway, WebAccelerator, and WOM 11.0.0 through 11.3.0 and 10.1.0 through 10.2.4, and PSM 11.0.0 through 11.4.1 and 10.1.0 through 10.2.4 and Enterprise Manager 3.0.0 through 3.1.1 and 2.1.0 through 2.3.0 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
The rsync daemon in F5 BIG-IP 11.6 before 11.6.0, 11.5.1 before HF3, 11.5.0 before HF4, 11.4.1 before HF4, 11.4.0 before HF7, 11.3.0 before HF9, and 11.2.1 before HF11 and Enterprise Manager 3.x before 3.1.1 HF2, when configured in failover mode, does not require authentication, which allows remote attackers to read or write to arbitrary files via a cmi request to the ConfigSync IP address.