ZDI-07-044: BakBone NetVault Reporter Scheduler Heap Overflow Vulnerability http://www.zerodayinitiative.com/advisories/ZDI-07-044.html July 25, 2007 -- CVE ID: CVE-2007-3911 -- Affected Vendor: BakBone -- Affected Products: BakBone NetVault Reporter 3.5 < Update4 -- TippingPoint(TM) IPS Customer Protection: TippingPoint IPS customers have been protected against this vulnerability since July 24, 2007 by Digital Vaccine protection filter ID 5215. For further product information on the TippingPoint IPS: http://www.tippingpoint.com -- Vulnerability Details: This vulnerability allows remote attackers to execute arbitrary code on systems with affected installations of BakBone NetVault Reporter. User interaction is not required to exploit this vulnerability. The specific flaw exists both within the scheduler client (clsscheduler.exe) listening on TCP port 7978 and the scheduler server (srvscheduler.exe) listening on TCP port 7977. In both cases an exploitable heap corruption can occur during the processing of overly long filename arguments to the "GET" and "POST" requests. Code execution is possible under the context of the SYSTEM user. When searching for a termination/whitespace character ("\r\t\n") a heap chunk is being used to hold the data. Due to the lack of bounds checking on this heap chunk an overflow occurs when a long string without any of the above special characters are encountered. The vulnerable code appears below. 0x00466C07 mov al, [esi+ebp] 0x00466C0A cmp al, 20h 0x00466C0C jz short loc_466C84 0x00466C0E cmp al, 9 0x00466C10 jz short loc_466C84 0x00466C12 cmp al, 0Ah 0x00466C14 jz short loc_466C84 0x00466C16 cmp al, 0Dh 0x00466C18 jz short loc_466C84 0x00466C1A push 1 0x00466C1C inc esi 0x00466C1D push 1 0x00466C1F lea edx, [esi+ebp] ; heap chunk 0x00466C22 push edx ; readfds 0x00466C23 mov ecx, edi 0x00466C25 call sub_4645C0 ; recv 1 byte 0x00466C2A cmp eax, 0FFFFFFFFh 0x00466C2D mov [ebx+272Ch], eax 0x00466C33 jnz short loc_466C07 ;loop -- Vendor Response: BakBone has addressed this issue in NetVault Report Manager v3.5 Update4 available for download from: http://www.bakbone.com/products/downloads/default.asp -- Disclosure Timeline: 2007.02.23 - Vulnerability reported to vendor 2007.07.24 - Digital Vaccine released to TippingPoint customers 2007.07.25 - Public release of advisory -- Credit: This vulnerability was discovered by Tenable Network Security. -- About the Zero Day Initiative (ZDI): Established by TippingPoint, a division of 3Com, The Zero Day Initiative (ZDI) represents a best-of-breed model for rewarding security researchers for responsibly disclosing discovered vulnerabilities. Researchers interested in getting paid for their security research through the ZDI can find more information and sign-up at: http://www.zerodayinitiative.com The ZDI is unique in how the acquired vulnerability information is used. 3Com does not re-sell the vulnerability details or any exploit code. Instead, upon notifying the affected product vendor, 3Com provides its customers with zero day protection through its intrusion prevention technology. Explicit details regarding the specifics of the vulnerability are not exposed to any parties until an official vendor patch is publicly available. Furthermore, with the altruistic aim of helping to secure a broader user base, 3Com provides this vulnerability information confidentially to security vendors (including competitors) who have a vulnerability protection or mitigation product. CONFIDENTIALITY NOTICE: This e-mail message, including any attachments, is being sent by 3Com for the sole use of the intended recipient(s) and may contain confidential, proprietary and/or privileged information. Any unauthorized review, use, disclosure and/or distribution by any recipient is prohibited. If you are not the intended recipient, please delete and/or destroy all copies of this message regardless of form and any included attachments and notify 3Com immediately by contacting the sender via reply e-mail or forwarding to 3Com at postmaster (at) 3com (dot) com. [email concealed]