CVE-1999-0835: Critical severity IBM AIX vulnerability
Denial of service in BIND named via malformed SIG records.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Compensating control
Restrict access to the DNS service (named) at the network perimeter. Block or allow only trusted source IP ranges to reach UDP/TCP port 53 for affected hosts (IBM AIX, SCO OpenServer, SunOS, Xinuos UnixWare). Apply rate-limiting on DNS queries from untrusted networks to reduce exposure to denial-of-service from malformed SIG records.
- Compensating control
Deploy network-level filtering / IDS/IPS rules to detect and drop malformed DNS SIG records before they reach BIND named. Monitor for and block traffic patterns that include malformed or unusual SIG RRs.
- Operational
Monitor named logs and network traffic for signs of crashes or malformed SIG records. Collect crash dumps and packet captures for any trigger events to support diagnosis and vendor reporting.
- Operational
Apply vendor-supplied patches or updates for BIND/named on affected platforms (IBM AIX, SCO OpenServer, SunOS, Xinuos UnixWare) as soon as a fix is released by the vendor. Until a fix is available, keep affected DNS servers isolated or behind protective controls described above.
Event History
Frequently Asked Questions
What is the severity of CVE-1999-0835?
CVE-1999-0835 is considered a denial of service vulnerability affecting BIND named.
How do I fix CVE-1999-0835?
To fix CVE-1999-0835, update BIND to a version where this vulnerability is patched.
What systems are affected by CVE-1999-0835?
CVE-1999-0835 affects systems running certain versions of IBM AIX, Xinuos OpenServer, and Sun SunOS.
Can CVE-1999-0835 be exploited remotely?
Yes, CVE-1999-0835 can be exploited remotely to cause a denial of service.
What are the symptoms of an attack exploiting CVE-1999-0835?
The symptoms of an attack exploiting CVE-1999-0835 include loss of service for DNS queries handled by the affected BIND server.