Malicious PDF — malware analysis report

Static analysis result for SHA-256 b452c327e385ba9c…

MALICIOUS

PDF

76.8 KB Created: 2021-10-08 21:08:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f660fbf1dfe86ea5ef1655e66c8cb7bd SHA-1: 9a8089a4578b5c27ec479dab4ef9017a7cbbdf83 SHA-256: b452c327e385ba9c592aac8529a0d1601429ddbc03f94699456a239638cb8d99
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan threat. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights this behavior, and the presence of external URIs further supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5565

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crysiq.ru/uplcv?utm_term=civil+engineering+entrance+exam+reviewer+pdf PDF link annotation
    • https://egf.tw/test2/images/file/dokigo.pdfIn PDF document text
    • http://cualuoiskydoor.com/webroot/img/files/wanosoxonireduzesuwunap.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/1120103551.pdfIn PDF document text
    • http://altus.pl/userfiles/file/30946249214.pdfIn PDF document text
    • http://supair-lux.hu/ckfinder/userfiles/files/bigijeniwake.pdfIn PDF document text
    • http://bidmitt.com/img/files/file/54535917866.pdfIn PDF document text
    • https://transmilenio.net/datamont/userfiles/file/71086880085.pdfIn PDF document text
    • https://patriciogaete.com/upload/file/18724792593.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/755851e4427279d3c85859a6191c4354/64704741130.pdfIn PDF document text
    • http://ap116.ru/userfiles/file/50416551347.pdfIn PDF document text
    • https://chuyennhakienvangvn.net/upload/files/38462836023.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210911191027066.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161490efa2e86b---wotobuxosa.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/ea46cc098663adfa2bc5cd2dc006ff16/nefexenotosidata.pdfIn PDF document text
    • http://viorina-deko.com/images/file/wesimimudijejavoxixotuje.pdfIn PDF document text
    • https://mandarinkinesiska.com/userfiles/file/32116394719.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/d49f6f7460bbbe2726a0c7fa8466db0b/buzamalawemaxaruzikusem.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/dupotolidoxevazono.pdfIn PDF document text
    • http://bielle-srl.com/userfiles/files/fekigorituroje.pdfIn PDF document text
    • http://kibbkw.com/uploads/files/77023288193.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/62777547005.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/15021171294.pdfIn PDF document text
    • http://ieeepes-thailand.org/app/webroot/files/files/luritazusidezije.pdfIn PDF document text
    • http://oralrem.kz/ckfinder/userfiles/files/84371884499.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/ebaa85ac3c88cc54cbba02758a6aa1ce/94535234029.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE248 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA5A 19940 bytes
SHA-256: 535a31c3273fa538ffa1c0f3f42ad90c103fbb756efe57d30c5ee10866561be0