REDHAT-BUG-2477116: Buffer Overflow
NGINX Plus and NGINX Open Source have a vulnerability in the ngxhttprewritemodule module. This vulnerability exists when the rewrite directive is followed by a rewrite, if, or set directive and an unnamed Perl-Compatible Regular Expression (PCRE) capture (for example, $1, $2) with a replacement string that includes a question mark (?). An unauthenticated attacker along with conditions beyond its control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, for systems with Address Space Layout Randomization (ASLR ) disabled, code execution is possible. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Remove
Remove
ngx_http_rewrite_modulefrom your environment.If the ngx_http_rewrite_module is not required, disable or remove the ngx_http_rewrite_module from the NGINX build/configuration to eliminate the vulnerable component until a vendor-provided fix is available.
Event History
Frequently Asked Questions
What is the severity of REDHAT-BUG-2477116?
The severity of REDHAT-BUG-2477116 is classified as high due to potential unauthorized access to sensitive data.
How do I fix REDHAT-BUG-2477116?
To fix REDHAT-BUG-2477116, update NGINX Plus or NGINX Open Source to the latest version that addresses this vulnerability.
What products are affected by REDHAT-BUG-2477116?
REDHAT-BUG-2477116 affects NGINX Plus and NGINX Open Source installations.
What vulnerability exists in REDHAT-BUG-2477116?
REDHAT-BUG-2477116 exposes vulnerabilities in the ngx_http_rewrite_module module related to improper handling of regex captures.
Is there a workaround for REDHAT-BUG-2477116?
A workaround for REDHAT-BUG-2477116 may involve disabling certain rewrite directives until the software is updated.