Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c53a0219a3afd66…

MALICIOUS

PDF

83.0 KB Created: 2021-09-16 23:14:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e152c23ebc7c41414880fd12a2ae89e0 SHA-1: 45c3faf1cd4e65c2574af6bc2a3452aa4f6e5dfc SHA-256: 6c53a0219a3afd66e4b11fe55e50c18ac931716f3524a47feb53dc7146ec2e2b
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to other PDF files, many hosted on domains flagged as potentially compromised or disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish or deliver further malware. The primary attack pattern observed is the use of a link farm to obscure the ultimate destination and potentially evade initial detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://parvazyab.com/basefile/api203/files/tifuwonoje.pdf In PDF document text
    • http://canhtoanland.com/upload/files/93071275345.pdfIn PDF document text
    • http://rezidencianestor.sk/app/webroot/files/ckeditor/files/58776902858.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e675c6aa8---12362550974.pdfIn PDF document text
    • http://sino-web.net/filespath/files/20210908061138.pdfIn PDF document text
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/kifedeman.pdfIn PDF document text
    • https://greengenome.in/admin/userfiles/file/kujuveviporu.pdfIn PDF document text
    • http://studiofagiani.eu/userfiles/files/kimasunofo.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/27daa3ad0fe17ccff9d0eec9616ecf4f/tupikikemosox.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134ceaeb5c36---64818421343.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/23530901350.pdfIn PDF document text
    • https://granitabrasive.hu/editor_up/wopuju.pdfIn PDF document text
    • https://tsolisp.com/files/file/gogerawepimobabamufaru.pdfIn PDF document text
    • http://tetobox-budapest.hu/uploads/files/19470250272.pdfIn PDF document text
    • https://tradingphrases.com/userfiles/files/jemovopefewezavesek.pdfIn PDF document text
    • http://occahomesearch.com/userfiles/files/vikotufup.pdfIn PDF document text
    • https://www.xyoaa.org/sites/default/files/files/vorubizigo.pdfIn PDF document text
    • https://sassanoproperties.com/FCKeditor/file/674274366.pdfIn PDF document text
    • https://anandalaya.in/resources/file/51981935032.pdfIn PDF document text
    • https://aldaserwis.pl/ckfinder/userfiles/files/69061029496.pdfIn PDF document text
    • https://lecormier-menuiserie.com/www/upload/files/poxagos.pdfIn PDF document text
    • https://samsungklimamodelleri.com/upload/ckfinder/files/mukavoxubukazi.pdfIn PDF document text
    • http://sun-green.be/ckfinder/userfiles/files/lanewososat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+send+a+ringtone+from+iphone+to+androidPDF 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_off0000dae6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE6 19452 bytes
SHA-256: 0d188bd2ca055b0683fc872b566e1ae06a017c63c8dabad3e7f6f1c94e5dd083
font_01_sfnt_off00010d09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012520.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12520 10976 bytes
SHA-256: 842a0cb07b710f9ab5783ac5f1631a8e7a51a68b9b274ffe45deeba445edf059