ext/openssl/ossl_ocsp.c in Ruby 1.8 and 1.9 does not properly check the return value from the OCSP_basic_verify function, which might allow remote attackers to successfully present an invalid X.509 certificate, possibly involving a revoked certificate.
httputils.rb in WEBrick in Ruby 1.8.1 and 1.8.5, as used in Red Hat Enterprise Linux 4 and 5, allows remote attackers to cause a denial of service (CPU consumption) via a crafted HTTP request. NOTE: this issue exists because of an incomplete fix for CVE-2008-3656.
resolv.rb in Ruby 1.8.5 and earlier, 1.8.6 before 1.8.6-p287, 1.8.7 before 1.8.7-p72, and 1.9 r18423 and earlier uses sequential transaction IDs and constant source ports for DNS requests, which makes it easier for remote attackers to spoof DNS responses, a different vulnerability than CVE-2008-1447.
The REXML module in Ruby 1.8.6 through 1.8.6-p287, 1.8.7 through 1.8.7-p72, and 1.9 allows context-dependent attackers to cause a denial of service (CPU consumption) via an XML document with recursively nested entities, aka an "XML entity explosion."
The regular expression engine (regex.c) in Ruby 1.8.5 and earlier, 1.8.6 through 1.8.6-p286, 1.8.7 through 1.8.7-p71, and 1.9 through r18423 allows remote attackers to cause a denial of service (infinite loop and crash) via multiple long requests to a Ruby socket, related to memory allocation failure, and as demonstrated against Webrick.
Ruby 1.8.5 and earlier, 1.8.6 through 1.8.6-p286, 1.8.7 through 1.8.7-p71, and 1.9 through r18423 does not properly restrict access to critical variables and methods at various safe levels, which allows context-dependent attackers to bypass intended access restrictions via (1) untrace_var, (2) $PROGRAM_NAME, and (3) syslog at safe level 4, and (4) insecure methods at safe levels 1 through 3.
Algorithmic complexity vulnerability in the WEBrick::HTTPUtils.split_header_value function in WEBrick::HTTP::DefaultFileHandler in WEBrick in Ruby 1.8.5 and earlier, 1.8.6 through 1.8.6-p286, 1.8.7 through 1.8.7-p71, and 1.9 through r18423 allows context-dependent attackers to cause a denial of service (CPU consumption) via a crafted HTTP request that is processed by a backtracking regular expression.
The dl module in Ruby 1.8.5 and earlier, 1.8.6 through 1.8.6-p286, 1.8.7 through 1.8.7-p71, and 1.9 through r18423 does not check "taintness" of inputs, which allows context-dependent attackers to bypass safe levels and execute dangerous functions by accessing a library using DL.dlopen.
Integer overflow in the rb_ary_fill function in array.c in Ruby before revision 17756 allows context-dependent attackers to cause a denial of service (crash) or possibly have unspecified other impact via a call to the Array#fill method with a start (aka beg) argument greater than ARY_MAX_SIZE. NOTE: this issue exists because of an incomplete fix for other closely related integer overflows.
Multiple integer overflows in the rb_str_buf_append function in Ruby 1.8.4 and earlier, 1.8.5 before 1.8.5-p231, 1.8.6 before 1.8.6-p230, 1.8.7 before 1.8.7-p22, and 1.9.0 before 1.9.0-2 allow context-dependent attackers to execute arbitrary code or cause a denial of service via unknown vectors that trigger memory corruption, a different issue than CVE-2008-2663, CVE-2008-2664, and CVE-2008-2725. NOTE: as of 20080624, there has been inconsistent usage of multiple CVE identifiers related to Ruby. This CVE description should be regarded as authoritative, although it is likely to change.