Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cd4d0b941c9ca46…

MALICIOUS

PDF

69.3 KB Created: 2021-09-18 19:30:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: afd029bc87de3d7bc78bb57ebd6dc249 SHA-1: 5665d4e64b4e2d3e9cff2fdb1ede372dfcb27128 SHA-256: 9cd4d0b941c9ca469e20c2f34e3153b92adf07b05ba7b7799b3feab8cf24ce16
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to compromised CMS uploads and disposable hosting, often disguised with UTM parameters for SEO manipulation. The presence of numerous links to PDF files on various domains suggests an attempt to distribute malicious content or phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://bhk-aindling.com/userfiles/files/20694469584.pdf In PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/73014829167.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/63076501386.pdfIn PDF document text
    • http://biosystech.com/pdsFck/file/33127888012.pdfIn PDF document text
    • https://macintosh-szerviz-javitas.nuttydog.hu/ckfinder/userfiles/files/1694475752.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/tatokoxut.pdfIn PDF document text
    • http://zamaro.cz/images/fcke_files/file/vavanizuzipudigoferugopen.pdfIn PDF document text
    • http://www.fishandcosolicitors.com/uploads/files/mipalevufag.pdfIn PDF document text
    • https://eletmodguru.hu/files/files/zofuvalebofufono.pdfIn PDF document text
    • https://pasationtravellers.com/root/FCKeditor/file/vuguboditogaxezudino.pdfIn PDF document text
    • http://leguido.net/files/42508224538.pdfIn PDF document text
    • https://www.educationsexuelle-ecole.ch/ck/ckfinder/userfiles/files/99671664731.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/sexegudagokodotarulagize.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/7386948125.pdfIn PDF document text
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612f419a3ca4b---lafazisalopoz.pdfIn PDF document text
    • https://cubic.is/userfiles/file/74057081595.pdfIn PDF document text
    • https://teamcode.net/upload/files/74689954860.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6d095360a---72165337184.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/1e7b83f82b45e35a20837d1e87f5eaea/tizavaziwezozowe.pdfIn PDF document text
    • https://ladangmimpi.com/contents/files/jorosozokimilimoguzowas.pdfIn PDF document text
    • http://auburn-companies.com/userfiles/files/22477791517.pdfIn PDF document text
    • http://damnoen.com/ckfinder/pho/files/66352410115.pdfIn PDF document text
    • http://termosystem.pl/userfiles/file/segujofafug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=gta+5+download+for+android+free+downloadPDF 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_off0000b30b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB30B 10436 bytes
SHA-256: fe57d6a7f916666082671ef8f3b70ca6ea1e1173fdce2c67f8f6bb227f9ca51d
font_01_sfnt_off0000caf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAF1 14504 bytes
SHA-256: 4b9eb7fe5fd776db4a2f4fb017fa21fca97d915b3f9f657bb46c058e79a06b15
font_02_sfnt_off0000ef42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1