Malicious PDF — malware analysis report

Static analysis result for SHA-256 773dc83498bbe491…

MALICIOUS

PDF

73.5 KB Created: 2021-09-24 17:03:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 534afcd44048a226ef7670e62d18e8bc SHA-1: 93f4e3139ad58fd10d7cf7fb8124b797944cfc7e SHA-256: 773dc83498bbe49129f466732b66872372813a602f72d8e0bf9a72b62870a7e5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links, many pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to redirect users to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • 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 http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144087825c7c---zusunavotito.pdf
    • https://inprovitcaribe.com/ckfinder/userfiles/files/32555264627.pdf
    • https://12waktu.com/contents/files/32154157853.pdf
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/48002670553.pdf
    • https://organicfertilizerproduction.com/d/files/dofutopedoxadugim.pdf
    • http://murzilka.biz/images/uploads/file/korexizasojonuvelaw.pdf
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161455516b69a9---gotizitazofof.pdf
    • https://soechi.net/userfiles/file/94028498425.pdf
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614966ec8b0cf---kewetewuzosubokoju.pdf
    • https://zweefvlieg.net/userfiles/file/59964728073.pdf
    • http://fullgame.hu/uploads/files/27298253725.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16141ba5398aff---lanuwafigifugizogu.pdf
    • https://champion-osk.pl/userfiles/file/jiburumagarixarasijiwox.pdf
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/52482369961.pdf
    • http://jagodkaprzedszkole.pl/userfiles/file/78804458147.pdf
    • https://meritumptt.pl/dokumenty/file/73327714965.pdf
    • http://ohana1bbq.com/uploads/files/totifanezejo.pdf
    • http://chunmianxian.com/upfolder/e/files/20210917110648.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/ksgmk1cc632kff02iv67qv2smj/56176890.pdf
    • http://husplaza.hu/editor_up/21669137652.pdf
    • https://wineart.online/userfiles/file/92480876583.pdf
    • https://karlschool.org/uploads/files/202109161210224972.pdf
    • https://2b3la571ga-70p.com/contents/files/58484878585.pdf
    • http://www.flamanville-76.fr/upload/file/wemuxegavajexekifu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=instagram+photo+id+viewer
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b6f5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB6F5 16792 bytes
font_01_sfnt_off0000cf0c.bin
1ba514b0825e1db2110e7d748872a235748e66f081a29e7e64b091f044aef8e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF0C 10896 bytes
font_02_sfnt_off0000e7e6.bin
8de8c0f472d3f68d94f27e5161c39af1a30e23bc87087b3f9e6e5414c2af2eb1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E6 18256 bytes