Malicious PDF — malware analysis report

Static analysis result for SHA-256 872b6bca77fade6a…

MALICIOUS

PDF

80.7 KB Created: 2021-09-23 01:05:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3176e66bcba3860fb4ec0ec40eb34fd4 SHA-1: 889f097a5fef10682ea95aa30cd470f8715d7aab SHA-256: 872b6bca77fade6a868a3b5b175ae92555e88c6aa34003ecce813ced528e3582
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO abuse. The presence of multiple external URIs and link farm heuristics supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://krukaiart.com/userfiles/files/kawazazowikogarafunubizor.pdf In PDF document text
    • http://cozycornerexpress.com/uploads/files/wupevegisurateresiminazi.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/31408191894.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/161347404f2789---gijaronibotilexu.pdfIn PDF document text
    • http://mirsistem.com/depo/sayfaresim/file/xebalerarifedaviselu.pdfIn PDF document text
    • https://adamant54.ru/userfiles/files/vadorukubuletuviduzapul.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/27450647243.pdfIn PDF document text
    • http://hicoweld.com/shop/fck_file/file/22054394120.pdfIn PDF document text
    • https://evrenmentese.com/upload/ckfinder/files/lipinasobubugalupaf.pdfIn PDF document text
    • https://rzfmuhasebe.com/userfiles/file/nopitis.pdfIn PDF document text
    • http://dgjst.com/upfile/file/vewutasajitewikaf.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/21897792662.pdfIn PDF document text
    • http://falconfam.com/ckfinder/userfiles/files/53237704135.pdfIn PDF document text
    • https://www.privathospitaletkollund.com/ckfinder/userfiles/files/20039509907.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/33244173224.pdfIn PDF document text
    • http://litroshaber.net/resimler/files/guvaponojalutitis.pdfIn PDF document text
    • https://cplastik.cz/data/cms/file/kofanisanemikunezaxi.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/bcqbdtabq5nsuumidhpq62umg0/regidinavilejok.pdfIn PDF document text
    • https://mama-light.net/business_school/uploads/file/jejepurunejigo.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd57c44426---waxevos.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/sekuruvuxifedipi.pdfIn PDF document text
    • https://greenvalleykerala.com/ckfinder/userfiles/files/xamuxuzevaxajapigop.pdfIn PDF document text
    • https://sharpconsulting.us/app/webroot/ckfinder/userfiles/files/tazokufadomiwazemi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=top+torrent+sites+for+gamesPDF 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_off0000d5e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E6 17888 bytes
SHA-256: 02a77122300b6f0a646adf1f737c0176c6d2e439031b32f4ed0219d3a636f5b0
font_01_sfnt_off0001047c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1047C 10616 bytes
SHA-256: 3291bda110873e8c3f839384e08e6b4cc319c1a9df94f0a3a8ac50f4ecb0abe4
font_02_sfnt_off00011ccd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CCD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1