cbcvebase.
CVE-2008-1898
published 2008-04-21

CVE-2008-1898: A certain ActiveX control in WkImgSrv.dll 7.03.0616.0, as distributed in Microsoft Works 7 and Microsoft Office 2003 and 2007, allows remote attackers to…

PriorityP268critical9.3CVSS 2.0
AVNACMAuNCCICAC
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
52.03%
98.8th percentile
A certain ActiveX control in WkImgSrv.dll 7.03.0616.0, as distributed in Microsoft Works 7 and Microsoft Office 2003 and 2007, allows remote attackers to execute arbitrary code or cause a denial of service (browser crash) via an invalid WksPictureInterface property value, which triggers an improper function call.

Affected

3 ranges
VendorProductVersion rangeFixed in
microsoftoffice
microsoftoffice
microsoftworks

Detection & IOCsextracted from sources · hover to see the quote

filenameWkImgSrv.dll
other0x0A0A0A0A
other168430090
other0x0C0C0C0C
other202116108
bytes
%u0A0A%u0A0A
bytes
%u9090%u9090%u9090%u9090%u9090%uE8FC%u0044%u0000%u458B%u8B3C%u057C%u0178%u8BEF%u184F%u5F8B%u0120%u49EB%u348B%u018B%u31EE%u99C0%u84AC%u74C0%uC107%u0DCA%uC201%uF4EB%u543B%u0424%uE575%u5F8B%u0124%u66EB%u0C8B%u8B4B%u1C5F%uEB01%u1C8B%u018B%u89EB%u245C%uC304%uC031%u8B64%u3040%uC085%u0C78%u408B%u8B0C%u1C70%u8BAD%u0868%u09EB%u808B%u00B0%u0000%u688B%u5F3C%uF631%u5660%uF889%uC083%u507B%u7E68%uE2D8%u6873%uFE98%u0E8A%uFF57%u63E7%u6C61%u0063
  • Monitor for ActiveX instantiation of WkImgSrv.dll and assignment of a negative integer or the specific heap-spray values (168430090 / 0x0A0A0A0A for IE7, 202116108 / 0x0C0C0C0C for IE6) to the WksPictureInterface property.
  • Heap spray detection: look for large memory regions filled with repeated 0x0A bytes (IE7 vector) or 0x05 bytes (IE6 vector) targeting address 0x0A0A0A0A or 0x0C0C0C0C respectively.
  • The exploit delivers an HTML file (default name msf.html) containing JavaScript heap spray and an ActiveX object invoking WksPictureInterface; inspect web traffic or dropped files for this pattern.
  • The crash/exploitation path involves a bad virtual-call: EAX is set to the attacker-controlled integer, [EAX] is dereferenced into ECX, then CALL [ECX+0x30] is executed — watch for access violations at 0x0A0A0A0A or 0x0C0C0C0C in browser processes.
  • ·The heap-spray integer value must be changed depending on the target IE version: 168430090 (0x0A0A0A0A) for IE 7, 202116108 (0x0C0C0C0C) for IE 6.
  • ·The ActiveX control is not marked safe for scripting, so the attack vector requires the attacker to choose an appropriate delivery mechanism (e.g., a crafted HTML file rather than a drive-by from an arbitrary site).
  • ·Standard NOP-sled (0x90) heap spray cannot be used because 0x90909090 is an invalid memory address in this context; the spray byte must be a single-byte instruction whose 4-byte repetition forms a valid, self-referencing address.

CVSS provenance

nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
vulncheck9.3CRITICAL
CVEs like this are exactly what “Exploited This Week” covers.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.