cbcvebase.
CVE-2012-2539
published 2012-12-12

CVE-2012-2539: Microsoft Word 2003 SP3, 2007 SP2 and SP3, and 2010 SP1; Word Viewer; Office Compatibility Pack SP2 and SP3; and Office Web Apps 2010 SP1 allow remote…

PriorityP181high7.8CVSS 3.1
AVLACLPRNUIRSUCHIHAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2022-04-18
Exploited in the wild
EPSS
53.16%
98.9th percentile
Microsoft Word 2003 SP3, 2007 SP2 and SP3, and 2010 SP1; Word Viewer; Office Compatibility Pack SP2 and SP3; and Office Web Apps 2010 SP1 allow remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via crafted RTF data, aka "Word RTF 'listoverridecount' Remote Code Execution Vulnerability."

Affected

5 ranges
VendorProductVersion rangeFixed in
microsoftoffice_web_apps
microsoftsharepoint_server
microsoftword
microsoftword
microsoftword

Detection & IOCsextracted from sources · hover to see the quote

hash3fbffe29252df6a87f37962afe72576ea2a7a5540d6c7993cbbff265fcd2734d
otherSnort SID 24974
otherSnort SID 24975
snort
alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET WEB_CLIENT Microsoft Rich Text File .RTF File download with invalid listoverridecount"; flow:established,to_client; file.data; content:"|5c|listoverridetable"; distance:0; content:"|5c|listoverride|5c|"; fast_pattern; content:"|5c|listoverridecount"; isdataat:2,relative; pcre:"/^(?:0*?[19]\d|[^190])/R"; reference:cve,2012-2539; classtype:attempted-user; sid:2018315; rev:7; metadata:affected_product Web_Browsers, affected_product Web_Browser_Plugins, attack_target Client_Endpoint, created_at 2012_12_12, cve CVE_2012_2539, deployment Perimeter, signature_severity Major, tag Web_Client_Attacks, updated_at 2024_03_13;)
  • The exploitation vector is the RTF `\listoverridecount` field. Only values 0, 1, or 9 are legal; any other value indicates a potentially malicious or malformed document exploiting CVE-2012-2539.
  • Detect RTF files containing `\listoverridetable` followed by `\listoverride\` and `\listoverridecount` with a value that does not match 0, 1, or 9 (regex: `/^(?:0*?[19]\d|[^190])/R`).
  • The vulnerability is triggered via crafted RTF data delivered to Microsoft Word; network-level detection should focus on HTTP responses delivering RTF files with invalid `listoverridecount` values (flow: established, to_client).
  • The Snort rule message string 'listoverridecount' in the rule message can be used to identify existing coverage and correlate alerts to this CVE.
  • ·Some legitimate RTF-generating software may produce `\listoverridecount` values outside 0, 1, or 9, leading to false positives. The ClamAV signature was temporarily converted to a PUA signature for this reason before being re-enabled.

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C
vulncheck7.8HIGH
cisa7.8HIGH
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