Malicious PDF — malware analysis report

Static analysis result for SHA-256 31525217ab6f4357…

MALICIOUS

PDF

94.3 KB Created: 2021-10-05 16:02:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 34a8b708007e533616d08f6ebc312b71 SHA-1: ed9d269a8e731e1d8936929b8c910eb4e4a4da7e SHA-256: 31525217ab6f435765f5c0eaeee47939aee185d7587098800f6e523782e8924d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, characteristic of a link farm used for phishing or malware distribution. The presence of external URI indicators and compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://smidgel.ru/uplcv?utm_term=agra+is+famous+for PDF link annotation
    • http://xn--nellieskche-0hb.de/userfiles/file/67389930199.pdfIn PDF document text
    • http://gavinlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vewivubus.pdfIn PDF document text
    • https://avela.md/userfiles/file/30336638817.pdfIn PDF document text
    • https://nguyenhungstone.com/uploads/image/files/zitekama.pdfIn PDF document text
    • http://belst.by/upload/file/bamojimoduvinosakonogemib.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/wowizexesexuzisekiwosipo.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/rolifivonuwafuz.pdfIn PDF document text
    • https://macauroommate.com/ckfinder/userfiles/files/zoxekumemigaxa.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613803afcfc4b---35790209157.pdfIn PDF document text
    • https://ibshospitals.com/userfiles/file/vegeguvewowadidubedef.pdfIn PDF document text
    • http://uforoi.com/app/webroot/uploads/files/tudelutaporitixevasozar.pdfIn PDF document text
    • http://marupi.de/UserFiles/File/73998204854.pdfIn PDF document text
    • http://farashimirooz.com/files/75619724154.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/56960722808.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/htt666hmhg40qd2td9chuidu60/54551900276.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/nlooar0qu37koof087n4tuia3c/lodudipidiwodazopaweto.pdfIn PDF document text
    • https://rafaela-motores.com/userfiles/file/tigosuz.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/69122547619.pdfIn PDF document text
    • http://mijinmotor.com/fckeditor/userfiles/file/58380851477.pdfIn PDF document text
    • http://gpsputhuppally.com/userfiles/file/ruxivubatodafo.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/58297544719.pdfIn PDF document text
    • 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_off00010512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10512 21352 bytes
SHA-256: 58cd1069b3e1631ba22e5e3972529a0d76ebdf19720f3c7926e165078faf1684
font_01_sfnt_off00013cce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000154e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154E5 10260 bytes
SHA-256: bc097800108154db36ad728869935f9db7762367242127f93db44d831a666915