Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd9547cf677f4ba2…

MALICIOUS

PDF

75.3 KB Created: 2021-09-06 18:47:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f1402d4a49c3a1755478b20f4a35a5e4 SHA-1: 37d4930bab74177c3432148449ccb06c6096cb34 SHA-256: dd9547cf677f4ba265de57ddf5e7b3cc16b1a140bd9424498ede6fb40483ab8b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malicious content or phish users. Although no scripts were explicitly extracted, the nature of the links and the detection suggest it likely leverages embedded JavaScript or exploits to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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 http://vkts.se/userfiles/file/55805916099.pdf In PDF document text
    • http://atmaircenter.com/lb/userfiles/files/90587046097.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b8808aaa702---89495991764.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d942c227e0---66915990056.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ff1fc8badda---81234737459.pdfIn PDF document text
    • http://dichvuhangngay.vn/uploads/image/files/31697098660.pdfIn PDF document text
    • https://digireg.dk/upload/kaleviputowotumepemo.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160dae1909cab0---gubigozoniduruwukaxiziwag.pdfIn PDF document text
    • http://szkolka-wiercioch.pl/files/file/rikedoradudasupazado.pdfIn PDF document text
    • http://canadapremiumlubes.com/survey/userfiles/files/7277410295.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/6918705777.pdfIn PDF document text
    • http://vietsinphar.com/uploads/files/panobezegonevowubuwexiri.pdfIn PDF document text
    • http://tortsurprise.ru/upload/redactor/files/90527963831.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/9514706988.pdfIn PDF document text
    • https://dadesigning.com/daduserfiles/files/lulinibijefos.pdfIn PDF document text
    • https://kompaspt2.com/contents/files/mumemitibanejeri.pdfIn PDF document text
    • https://newtech-utm.pl/userfiles/file/43061152302.pdfIn PDF document text
    • http://ohdiabo.net/images/ckeditor/files/42351553670.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/f1e587b22b0d8b267e49320023d8ec65/24934909860.pdfIn PDF document text
    • http://casadiriposomarsala.it/userfiles/files/74465902775.pdfIn PDF document text
    • http://mexvp.com/ckfinder/userfiles/files/wexiwulativezekiduxenalo.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/vov9op4ha8hr193sqqvi05p2h6/zupepujoz.pdfIn PDF document text
    • http://vinhomeshaiphong.net/app/webroot/img/files/binisulukebivebulaba.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210627063042750.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=range+servant+ball+washer+manualPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3B5 10780 bytes
SHA-256: 08dfc26455f32534ac4e7b533e4cd5fb61c121be4c6849e45670b3f1e486547c
font_01_sfnt_off0000dc71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC71 16700 bytes
SHA-256: d072d44ad4bd762acf3be28b1e6a299a1a1556453aed67a0119e788b544129f7
font_02_sfnt_off000107c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1