Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dcc0b66c07c7e42…

MALICIOUS

PDF

84.7 KB Created: 2021-10-05 14:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 1741ecf179284602cf975b54b377654b SHA-1: 577d121463e1415bd1e6dae321b563b0cb173449 SHA-256: 8dcc0b66c07c7e42954878a9620321322b6e84021657d8b6fa1e84d013194a1a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a machine learning classifier and ClamAV, indicating it is likely a phishing or malware distribution lure. The presence of numerous external URIs, many pointing to compromised CMS uploads or disposable hosting, suggests a link farm designed to redirect users. Although no scripts were explicitly extracted, the PDF structure and link farm nature are indicative of malicious intent, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://archism.ru/uplcv?utm_term=music+quiz+questions+2020 PDF link annotation
    • https://printsolutions.ro/uploads/wysiwyg/files/84729877779.pdfIn PDF document text
    • https://charterfori.ir/basefile/charterforiir/files/16795380972.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/16ptqitsh4b1m5ejka6blj56rr/gipadoj.pdfIn PDF document text
    • http://cachnhietcacham.vn/Images_upload/files/vobokil.pdfIn PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/mewoto.pdfIn PDF document text
    • http://xn--lv0az70cxar.tw/uploads/files/202109020026547995.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/tajaxit.pdfIn PDF document text
    • http://fractinvest.com/uploads/file/9465996668.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/70838566965.pdfIn PDF document text
    • https://www.solucionaesp.com/ckfinder/userfiles/files/40860283983.pdfIn PDF document text
    • http://xhzhengli.com/upload/kuzigukimubelinulo.pdfIn PDF document text
    • http://oawebserver.com/piceditor/file/sukusoverovegefiramebas.pdfIn PDF document text
    • http://trongtinpc.com/luutru/files/42714524152.pdfIn PDF document text
    • https://huanghecables.com/d/files/bapukom.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/kuxajejuxagopixexof.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/69970716411.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/1567640412.pdfIn PDF document text
    • http://tentauto23.ru/ckfinder/userfiles/files/96718132347.pdfIn PDF document text
    • http://lamekatus.ee/uploads/ckeditor/files/niderogigidoxomabopiro.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614114889d1dc---87121235351.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/25218524014.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202109061216524063.pdfIn PDF document text
    • https://alpinashop.rudy-ra.com/files/gijate.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16152a3c176d20---21509983752.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_off0000e12e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12E 10456 bytes
SHA-256: 2f985ce6ab95b570c56162a94b27519581fec9674b67e695fc7fc8a707e6d3dd
font_01_sfnt_off0000f92f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF92F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011141.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11141 20040 bytes
SHA-256: e168fa428b020393b75946fdec2eb09360553655f3d94d4d151e286630d6e35c