Mitigating Remote Code Execution in "HTTP.sys" (CVE-2015-1635)
A critical Windows vulnerability in its HTTP stack ("HTTP.sys"), which was resolved in a recent Microsoft's Patch Tuesday release, could allow remote attackers to execute code on an IIS server with the privileges of the System account. A Proof-of-Concept code to check the existence of this vulnerability was soon to follow. Remote attackers could exploit the way "HTTP.sys" parses requests with a Range header including a very large byte range to crash the server or potentially run their shellcode.
http://www.exploit-db.com/exploits/36773/
POC Information
Bug details according to the POC
More details on the available patch could be found in Microsoft’s security builletin MS15-034:
https://technet.microsoft.com/library/security/MS15-034
Following user-defined signature will detect and mitigate attempts to exploit this vulnerability while using ASM.
ASM versions including and above 11.2.x:
headercontent: "range"; nocase; re2:"/bytes\s*=.*?[0-9]{10,}\b/Hi";
ASM versions including and below 11.1.x:
headercontent: "range"; nocase; pcre:"/bytes\s*=.*?[0-9]{10,}\b/Hi";
Published Apr 15, 2015
Version 1.0
Tarik_B_Nimbostratus
HI Maxim, As a beginner, can you explain me how to implement this solution in the ASM (BIGIP 10.2.4)- https://support.f5.com/kb/en-us/products/big-ip_asm/manuals/product/config_guide_asm_10_2_0/asm_attack_sigs.html1047564
- MegaZone
SIRT
Additonal mitigations have been published: Using iRules - https://devcentral.f5.com/s/articles/using-irules-to-mitigate-microsofts-ms15-034-cve-2015-1635-range-vulnerability Using LineRate - https://devcentral.f5.com/s/articles/linerate-range-header-attack-mitigation
