Malicious PDF — malware analysis report

Static analysis result for SHA-256 62428267ba985c6f…

MALICIOUS

PDF

79.8 KB Created: 2021-08-29 09:11:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 52d4ed5bffbcb176a1cf2db1e890e8b1 SHA-1: 12ef940bcd4d93fe23f57fb74008627caa23ef18 SHA-256: 62428267ba985c6fcfa8494e12dfed09e75d50da3b8eca8148911c40dcb2917d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating it likely contains exploit code or phishing content. It functions as a link farm, presenting numerous URLs that point to other PDF files hosted on various domains, some of which appear to be compromised CMS installations. This suggests a multi-stage attack where the initial PDF serves to redirect users to potentially malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 https://aczv.fr/userfiles/file/towuw.pdf In PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/85sof2n25r2i0ou6c8vtsligog/14473081635.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c217cd69f63---vebofusevegukimitusirik.pdfIn PDF document text
    • http://elma1.ru/!upload/files/lerovunabaxakorewujogiv.pdfIn PDF document text
    • http://mobilesamara.com/img/files/file/49964586308.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c4c49f2d2b0---46222808090.pdfIn PDF document text
    • http://kpotplace.com/uploads/files/42988640300.pdfIn PDF document text
    • http://dailymaytrogiang.com/userfiles/files/jajepewefobeko.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/26741533013.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/870c810006d92a730818a8bda9acf549/femejufilu.pdfIn PDF document text
    • http://ritadas.in/userfiles/file/73233645220.pdfIn PDF document text
    • http://webinaris.biz/ckfinder/userfiles/publics/files/lizamesoxumi.pdfIn PDF document text
    • https://j26clean.com/upload/files/67015424806.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160916908173b1---8130787165.pdfIn PDF document text
    • http://www.emploi.nat.tn/ckeditor/ckfinder/userfiles/files/zefudupulivusizipuvulo.pdfIn PDF document text
    • http://csc010.com/userfiles/file/20210612114526_4phxnv.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cad142a1c9---giworiradugiduke.pdfIn PDF document text
    • https://allianztc.ro/files/file/44178087661.pdfIn PDF document text
    • https://avphunter.ro/ckfinder/userfiles/files/78397958845.pdfIn PDF document text
    • http://abwmechanicsville.com/uploads/files/82806144166.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/t1jbe88p7vhv0goq3oko04nmph/dopurivinudomal.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/7730244634.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=the+sun+and+her+flowers+epubPDF 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_off0000d1af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e9c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9C1 17976 bytes
SHA-256: 455bfdc8bd8daaa5a088645d8ada6e99640cbd92a59d6c67e707e591f3b5a3a5
font_02_sfnt_off000118a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118A4 10692 bytes
SHA-256: a7bbfbe5cfb12fb8d6a6c1453bc37e260aec629ba3dad7d027c771323ae6219f