Malicious PDF — malware analysis report

Static analysis result for SHA-256 87e0c37c582cfda1…

MALICIOUS

PDF

108.1 KB Created: 2021-09-04 06:21:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0d8b54a1af91f6797b3072eebc83cb29 SHA-1: 663d1406aff44e233552eb594ca3a0b912d99fa4 SHA-256: 87e0c37c582cfda191f834ff31f84fd4673a70cc6387a7f48b05c12d552ded29
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to compromised websites, many of which host other PDF files. This behavior is indicative of a link farm designed to distribute malicious content or facilitate phishing attacks. The ML classifier and ClamAV detection strongly support its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160947f6f9ddd6---pedaxaw.pdf In PDF document text
    • http://alaskacounseling.org/clients/8/87/870ae3779d21e956d596131c1dd113ff/File/jofavusikuzubodukolufeti.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1611eb61c7d2c4---tasirukivuvomusoremidukeb.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1607221cf9d567---giwukazakenoma.pdfIn PDF document text
    • https://inmaabiladi.com/userfiles/files/nabemesapinidufupupug.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/molize.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/b2484a5b5b210424d313c03ab20c8b26/mogijekokoxisuvav.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/29633221440.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/97248914104.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abeeb7e5223---4620967926.pdfIn PDF document text
    • http://sxhk365.com/uploads/file///46334798556.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/fowuxewazawutaz.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/f8ndt9v82p0lktbhkd7d96f6u5/632672597.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/wusukezorubopinibunotepur.pdfIn PDF document text
    • http://evopizza.lt/ckfinder/userfiles/files/35291361882.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/6aig701q8kg61ft2t6227vq5r2/51394447039.pdfIn PDF document text
    • http://www.gabrielamaciel.net/images/content/file/2964087827.pdfIn PDF document text
    • http://tomaszfilipczak.pl/userfiles/file/96687836205.pdfIn PDF document text
    • http://fcraregistration.com/UploadedData/file/65861806818.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/f62a6157b0139c536578275541ab7df0/67084743564.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/93965387671.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/43flerplqd47ine0dmoucjqtu7/1029078721.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=schelling+saw+manualPDF 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_off000149d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000161ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x161ED 10620 bytes
SHA-256: de9c1ac272e0e96b83af1495aa4f12fd0348942910cc809118412e4eedbfc1ce
font_02_sfnt_off00017a08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17A08 15984 bytes
SHA-256: f81c273c463e7dbc7a8d72fd0e7edf57bb72738a42bcee677663fad42cbeb03a