Malicious PDF — malware analysis report

Static analysis result for SHA-256 70903b1593f76727…

MALICIOUS

PDF

77.1 KB Created: 2021-09-05 06:27:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8ece702c281089dd45c699184b889893 SHA-1: 9ef938c9b40950913cac820e3a20036861ed29f7 SHA-256: 70903b1593f76727180040c463238cbdbec492f125b29a69c9ab42dbd33c8b08
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites, suggesting an attempt to obscure the final destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 https://krisoc.ru/uplcv?utm_term=english+to+kannada+dictionary+free+download+pdf PDF link annotation
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/peu2pv5o213mki88gs98tfqf7m/ruguxufotogutoru.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/12742380403.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7951927471---junuzesudiwufig.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f35b07f8c3---79320704543.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a95fcb5d37d---28947852722.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0369e9ad75---21271769747.pdfIn PDF document text
    • http://hzbaoyan.com/images/upload/File/fadevutaziwesepo.pdfIn PDF document text
    • https://tenutaedone.com/filesUploads/file/ragusosilugebo.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/lusatunorena.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1629553796.pdfIn PDF document text
    • http://akademibt.com/resimler/files/bekokukuvuv.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/844937c345e62c0656d53ad234b25efc/gomipagivutonetu.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/dapumuguvufinowawodes.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202107081719372940.pdfIn PDF document text
    • https://satbietthu.com/luutru/files/fumasokesozisemif.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/45181626221.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/fkehsfptl0j1m934afbkl351pj/70556647263.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/43a83514a847ae0b5311047b91d4dfac/xebebafodi.pdfIn PDF document text
    • http://arserwood.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210508223229337681f9c6h9.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/rosivisabotijag.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160967640c010e---lulolijifaxibasiwo.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/aiuvgab1d7o170apco2d1nfqgi/sinufowuwu.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160f2ec32dcda4---71134620922.pdfIn PDF document text
    • https://kientrucqhouse.com/uploads/image/files/mowapekanitavumejutukuxeg.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/retukirasetigezisab.pdfIn PDF document text
    • 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_off0000c470.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC470 11172 bytes
SHA-256: ff00f7fad3be04ebc1cb90966dbbd97d0914ee0045a46b3efeb5fd6759b58083
font_01_sfnt_off0000de5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE5F 18308 bytes
SHA-256: d0d0295cfce2b77d09b40968eba315400295ebfe504ab39cfd096358c1d87f1e
font_02_sfnt_off00010e47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1