Malicious PDF — malware analysis report

Static analysis result for SHA-256 90d38a7eafafbb16…

MALICIOUS

PDF

78.7 KB Created: 2021-09-10 23:49:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 22fc410bbe5bbb49226b50274da5da70 SHA-1: 79ae8164430860fac2a904aa79a5f18723955364 SHA-256: 90d38a7eafafbb16afa875f7ebc259ce12248d960331063a54746bc658169e08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to compromised CMS upload storage and disposable hosting. The embedded URLs suggest an attempt to direct users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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
  • 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://immobilieninvestors.net/userfiles/file/zamebubunuva.pdf In PDF document text
    • http://sarljarry.com/userfiles/file/jokezabifirefap.pdfIn PDF document text
    • http://szjglaw.com/uploadfile/file/2021090212555173499.pdfIn PDF document text
    • https://cmoretv.com/userfiles/28173877378.pdfIn PDF document text
    • http://vhshf.de/File/vifibovesemume.pdfIn PDF document text
    • https://livres-d-art.com/ckfinder/userfiles/files/samudulakogivokom.pdfIn PDF document text
    • https://pmms-online.com/assets/file/gufolifiti.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/c7iuhe8nnnqieee02ur9q4kg82/1106610088.pdfIn PDF document text
    • http://incomsistema.ru/ckfinder/userfiles/files/moribinokevojokam.pdfIn PDF document text
    • http://18554080.com/userfiles/file/5736611691.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/95485783908.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/lapozafovaremowuvifuxut.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/86693994878.pdfIn PDF document text
    • http://moscowfashion.net/content/xuploadimages/file/66098978087.pdfIn PDF document text
    • https://aordonez.com/images/contenidos/files/67496300548.pdfIn PDF document text
    • http://emilymillerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/begavuwivodokezosuvum.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/218af71c59806fecaa551661c60fbebd/16596300684.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/50763557526.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/48114068013.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613002d626b8f---95299034369.pdfIn PDF document text
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/37911772418.pdfIn PDF document text
    • https://www.tamilsaga.com/ckfinder/userfiles/files/filufotamamaxawulub.pdfIn PDF document text
    • http://dealershop.es/camarasegovia/userfiles/file/8328003961.pdfIn PDF document text
    • http://haphadoor.com/upload/files/dudapaxamenifatid.pdfIn PDF document text
    • http://collegium-connect.nl/ckupload/files/89994119730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=revvl+4+unlockPDF 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_off0000d080.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD080 9984 bytes
SHA-256: 79c659bc07f7b3ebf4c33dccf883bf7917983ec7097c7d84e4271789503c63aa
font_01_sfnt_off0000e6d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6D5 17828 bytes
SHA-256: c35576e3e9cc02631b64b53eeb568233a1e6bae9527dac62afd11d53bda50da8
font_02_sfnt_off00011505.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11505 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1