Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbd0e29475e88c03…

MALICIOUS

PDF

71.4 KB Created: 2021-09-18 09:55:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ae2d2b868f0657d302ce0ba8af6205aa SHA-1: 4ae0f50ae6d01ec6abec20c2b62aecbc8497c9b8 SHA-256: dbd0e29475e88c034f0c18968d9ae25a5a93b2bbed426482f2d3f6e6e54eceff
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs that form a link farm, with several pointing to compromised CMS uploads or disposable hosting. The primary purpose appears to be directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://0975811252cool.linker.tw/files/muwosi.pdf In PDF document text
    • http://www.eurosecurimed.com/ckfinder/userfiles/files/98094179371.pdfIn PDF document text
    • http://snft.ro/media/file/16369056931.pdfIn PDF document text
    • https://thaiahpa.com/flash/files/xapulalezulijedunotexubar.pdfIn PDF document text
    • http://k-yoga.org/file_upload/spaw_upload/file/20210918110723.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/20963169656140753742546.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/85369942eec7f18674ebc9f80094eb1f/41611460502.pdfIn PDF document text
    • https://ekransamara.ru/files/jikotunarulobuxorigag.pdfIn PDF document text
    • https://nirmalujjwal.com/public/ckfinder/userfiles/files/75548878829.pdfIn PDF document text
    • http://kodemari.info/data/files/11635667588.pdfIn PDF document text
    • https://buzascsaba.hu/userFiles/file/2862440907.pdfIn PDF document text
    • http://9y.bfage.com/upload/files/20210915173033.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/kixibofogakulama.pdfIn PDF document text
    • http://mrybalko.ru/files/ruramiluturaxekemowixil.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/43382258068.pdfIn PDF document text
    • https://shreenathtechnologies.com/userfiles/file/22688076067.pdfIn PDF document text
    • http://lamekatus.com/uploads/ckeditor/files/pojanagelab.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161351a550200b---juriguwudibawabaxogumi.pdfIn PDF document text
    • http://chhattisgarhsanskritboard.in/sharpinstitute/images/files/67689703360.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/filokinofizalonudanugepot.pdfIn PDF document text
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/tederakag.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16136add7071d1---49217372031.pdfIn PDF document text
    • http://highdeal.linkeo.net/ckfinder/userfiles/files/basegagasusekefa.pdfIn PDF document text
    • http://cka-shiba.com/ckfinder/userfiles/files/98089869882.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=android+app+market+urlPDF 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_off0000b7a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7A8 10560 bytes
SHA-256: 5ff17ae3cb06e33b298b8753267557e23bc932654f13a84c65d602ac7ab85a4e
font_01_sfnt_off0000cfa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFA9 15912 bytes
SHA-256: d8420e27bc5671bdc4ecd871dd1ec17d64bedd455e87fd8446a72617aad3aba4
font_02_sfnt_off0000f880.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF880 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1