Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d6f1f86d73721d3…

MALICIOUS

PDF

85.1 KB Created: 2021-09-15 18:46:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 96c34a898d0a4fb71fb63c63f83259d0 SHA-1: b461d909d333715313d284fcd3c3cf27c9cf26a2 SHA-256: 8d6f1f86d73721d339703373dd53582ddd3e88830ce7f11090fd5c1d41b03c9f
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall detection indicate a phishing or SEO poisoning attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://wastran.ru/uplcv?utm_term=redmi+note+4+android+system+battery+drain PDF link annotation
    • https://songod.vn/uploads/image/files/2694638251.pdfIn PDF document text
    • http://qualityspices.in/ckuploads/files/divobodigonubutolavug.pdfIn PDF document text
    • http://www.fuchingrading.com/upload/file/76027805732.pdfIn PDF document text
    • https://dpengineers.info/admin/userfiles/file/30597066163.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/21033652802.pdfIn PDF document text
    • https://ph2020.org/ckfinder/userfiles/files/tatotogedixawemoz.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/sumibuferifiji.pdfIn PDF document text
    • http://kuppersbusch.hu/userfiles/files/tekeritivek.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d21adc5ee0---baxefufefagiburowidemo.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/vejojapesimu.pdfIn PDF document text
    • https://cebrium.ssnn.ro/images/bipasovibufitavexozeg.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/rabupapuderewilurax.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/161410e71713b6---kukisosepikikunife.pdfIn PDF document text
    • http://antitumor.org/filespath/files/20210902083100.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/fvta1o4rbrh76llthud43b7dpv/82866147714.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2cf58b6f2---wetipaz.pdfIn PDF document text
    • https://falconshipping-uae.com/userfiles/files/rufet.pdfIn PDF document text
    • http://incomsistema.ru/ckfinder/userfiles/files/15901704998.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/retomalu.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/81697519927.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/55045611732.pdfIn PDF document text
    • http://cautrucpalang.vn/webroot/img/files/meseralogoveted.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/66379212419.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f589c7db76---16810005007.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/a405640b8ae4b4a069ad61a7b336ba58/44766457306.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_off0000e928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE928 17096 bytes
SHA-256: 77747464343f49053a38e67096a1fcbf107174fbe5c6a69202a3a6b870e0153e
font_01_sfnt_off00011584.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11584 10740 bytes
SHA-256: 0ea3a5b4aff03ccb0493eb8333365118dadce8bf88ee5634989d325a85f5fa3d
font_02_sfnt_off00012e50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E50 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1