Malicious PDF — malware analysis report

Static analysis result for SHA-256 1860d3b3c7fe8e78…

MALICIOUS

PDF

69.6 KB Created: 2021-09-10 05:54:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: daedcd9a7ea94529d30ce3560371ef5d SHA-1: 2f949e2342dcf0aae5d7d1ac89afbf48524ed9b0 SHA-256: 1860d3b3c7fe8e78fee2a3e44f609e541de12c16aa60a06c8ae8e8cc1d9a1fdb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The presence of 'utm_term' parameters in some URLs suggests an attempt to track user clicks, common in phishing or malware distribution campaigns. No scripts were extracted, but the PDF structure itself facilitates redirection to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://philabc.ru/uplcv?utm_term=subway+surfers+free+characters PDF link annotation
    • http://andlupa.com/userfiles/file/36136854037.pdfIn PDF document text
    • https://madhubanindiancuisine.com/nbloom/fckuploads/file/rixiwupaved.pdfIn PDF document text
    • https://dehayemek.net/upload/ckfinder/files/57410203318.pdfIn PDF document text
    • http://zatacorp.com/upload/files/vuzowe.pdfIn PDF document text
    • http://dansensvenner.dk/imagesfile///40483396089.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16139496ccd1e1---pokug.pdfIn PDF document text
    • http://uleshuzatshop.hu/files/file/zogigegedesufeluduwexale.pdfIn PDF document text
    • https://bomando.bomsolar.com/uploadfiles/files/dogerupedujebume.pdfIn PDF document text
    • http://dragoniresorts.com/userfiles/6855329780.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/kolegex.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/sutel.pdfIn PDF document text
    • http://tianlanip.com/filespath/files/20210903142427.pdfIn PDF document text
    • https://ikincielinmak.com/upload/ckfinder/files/94583565820.pdfIn PDF document text
    • http://draftingfloorplan.com/ckfinder/userfiles/files/tulonuwidekukozikexuv.pdfIn PDF document text
    • http://optometrystaprzemysl.pl/userfiles/file/30309290246.pdfIn PDF document text
    • http://medianet2000.net/amm_prod/image_news_popup/file/kakupu.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/37a3ce1de8f1947c7c509acdb5b5fe60/gedazipuw.pdfIn PDF document text
    • https://foundationkuzmanov.com/files/85544173216.pdfIn PDF document text
    • http://eko-uklid.com/files/file/tasopobuzidav.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/99fd112a92c938a8ba7d916c72df33ac/58736696417.pdfIn PDF document text
    • https://sunriseinnjasper.com/nbloom/fckuploads/file/58821442967.pdfIn PDF document text
    • https://komunalno-vrgorac.hr/files/limodilajirav.pdfIn PDF document text
    • http://dakov.hu/_user/file/11756588022.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_off0000b316.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB316 14972 bytes
SHA-256: 428108288929e0586b14399bbc1487ba6e728f1dee1002cf3b14dd1cd53e2478
font_01_sfnt_off0000d8ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0D1 10584 bytes
SHA-256: 0fe8098cc3a854850f4b5ee517dc266f83fa600ad973473a7b259d26254f7434