Malicious PDF — malware analysis report

Static analysis result for SHA-256 4740ee03974db11b…

MALICIOUS

PDF

71.2 KB Created: 2021-09-10 03:33:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4c51a0414b54c030969597e55498f95d SHA-1: 63b9e216c8679e1c5030f002eb238ae8e8518095 SHA-256: 4740ee03974db11b1f35db885d885ed075c93176fdd91e44613991e20c79bf64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics fired, including PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM, confirming the presence of a link farm pointing to various domains, some of which appear to be compromised WordPress installations. The embedded URLs suggest a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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://synerhu.ru/uplcv?utm_term=hotstar+no+ad+apk PDF link annotation
    • http://shopsuathientu.com/uploads/userfiles/file/33699255123.pdfIn PDF document text
    • http://reginahajo.hu/_user/file/7174091218.pdfIn PDF document text
    • https://macintosh-szerviz-javitas.nuttydog.hu/ckfinder/userfiles/files/51809798099.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/34987041771.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/nidipe.pdfIn PDF document text
    • http://breakevenpoint.pl/uploads/editor/file/nozamizevosiperajopanom.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134487c4aac2---22142270443.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/7adda1eed08691c88507ac4b80a4a34a/xugijepafebasofetekoz.pdfIn PDF document text
    • http://viprealestatebrokers.com/userfiles/files/jixelejixan.pdfIn PDF document text
    • https://kuepancong.com/contents/files/88542173534.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/52687741783.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/kff1ulbjgdclm5m52984mfgmj5/fazilovepidadilanobawusib.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a936664fed---75586121401.pdfIn PDF document text
    • https://rakowka.pl/userfiles/file/vozawemobejajipixedusex.pdfIn PDF document text
    • https://autopsrus.aerovents.com/ckfinder/userfiles/files/16237623303.pdfIn PDF document text
    • http://thietbiantoanttk.com/uploads/files/judofanijufewo.pdfIn PDF document text
    • http://staropolski.net/Upload/file/58639282460.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/bopufofeso.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/labilenavovudivoti.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/89887966894.pdfIn PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/81609393054.pdfIn PDF document text
    • http://ucg-eg.com/userfiles/file/48854490001.pdfIn PDF document text
    • http://paddockj.com/user_data/editor/ckfinder/core/connector/php/upload/files/xopugon.pdfIn PDF document text
    • http://toanthinh.vn/webroot/img/files/51845778169.pdfIn PDF document text
    • http://canoeing.by/pics/files/89188161020.pdfIn PDF document text
    • https://tempegaring.com/contents/files/31987417608.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_off0000b833.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB833 15736 bytes
SHA-256: 502626cc598178edb738ac7289a611f1f1bab6563131c5c35d21634e18fc1781
font_01_sfnt_off0000e083.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE083 10200 bytes
SHA-256: 4380a1f9d9e5e145cd18256c3eb0025016d9f1e8be63bf819173c33baf25ce44
font_02_sfnt_off0000f773.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF773 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1