Malicious PDF — malware analysis report

Static analysis result for SHA-256 9861ac88f0adff94…

MALICIOUS

PDF

77.2 KB Created: 2021-09-18 11:08:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a3f31cadb2dcc160822146d37a7aa041 SHA-1: 1859f74c7552a35364b99ca4418a0570fc6095f5 SHA-256: 9861ac88f0adff945c664805e974df1e2e5c91d28d76cc9f3a27b92d0102d904
156 Risk Score

Malware Insights

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

The file is a PDF document identified as malicious by ML classifiers and ClamAV, specifically flagged as Pdf.Phishing.Trojan. It contains a link farm pointing to multiple domains, some of which are associated with compromised CMS uploads or appear to be disposable hosting. The primary goal seems to be directing users to download further malicious content via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://ifap.it/images/file/74114723039.pdf
    • https://naveenent.com/administrator/imagetemp/file/wanuniledopinut.pdf
    • http://www.logomarcanet.com/userfiles/file/wupiseranosimobirikasut.pdf
    • https://kubermatkaplay.com/ckfinder/userfiles/files/6831389167.pdf
    • https://podgoricki-klub.me/userfiles/file/vabedafeduxat.pdf
    • http://phoiinnhiet.com/images/uploads/files/76321745007.pdf
    • https://huuphongplastic.vn/uploads/images/files/nexaregadexosedosab.pdf
    • http://markone-tools.com/upload/files/19464488973.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612e988b2eb41---sutozubefol.pdf
    • http://rszm88.com/upfolder/e/files/20210918083057.pdf
    • http://sz-nuoyi.com/Upload/file/2021091514141732945.pdf
    • https://www.southdownscellars.co.uk/ckfinder/userfiles/files/jilabuwamaripudeteritujip.pdf
    • http://friulanapanini.com/images/file/23802234506.pdf
    • http://v-lukomorie.com/uploader/files/sijuroxipilutovipa.pdf
    • https://jamuiboe.com/webroot/upload_media/gadibigasotot.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614520bc19ec3---11953042006.pdf
    • https://kompaspt2.com/contents/files/pugiwejapibawikoxadobezik.pdf
    • http://architectureanddesign.it/userfiles/files/89593246260.pdf
    • http://drironcat.com/images/file/65829847068.pdf
    • http://plechotice.sk/tmp/file/88773851226.pdf
    • http://podhoru.cz/userfiles/file/madefajonotepevaxuro.pdf
    • https://triangle-electronics.com/assets/userfiles/file/geximitipon.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/bvbka9h9f0hkus0sc9oeg8asn6/74595503713.pdf
    • http://portalpr-b2b.es/img/user//file/_0272245001631825929.pdf
    • http://erbamedica.org/userfiles/files/nopigirepafatuwo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=background+video+recorder+app
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c83a.bin
8e7e4dccc57d2a7b5e6286ecd90477f5cd515ddecba327cc6daa12f9adbbbf52
pdf-font-stream PDF embedded font (sfnt) at offset 0xC83A 10688 bytes
font_01_sfnt_off0000e0b0.bin
9ba7499554e1cc752f46eee54c5996ac1c7683cbd48329e9cf37d84aa8a4165b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B0 17652 bytes
font_02_sfnt_off00010ea7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA7 16792 bytes