Malicious PDF — malware analysis report

Static analysis result for SHA-256 04b165f45151a5fa…

MALICIOUS

PDF

81.7 KB Created: 2021-09-18 04:49:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: fa8cca6896d68cb26c3cb686c86fd4f2 SHA-1: 66788f9331461c058650536cede2334797e53ef3 SHA-256: 04b165f45151a5fad462e665560c96c46cb1cf0d5b31283552f680ed5a580a10
126 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to disposable domains, consistent with a link farm used to distribute malicious content or phish for credentials. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly indicates this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://snailgame.ru/upload/files/20210904020008.pdf In PDF document text
    • https://premiersuli.hu/files/files/mopidivajavesor.pdfIn PDF document text
    • http://vagtteam.com/userfiles/Files/56840136219.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16136c1c31726d---70253701445.pdfIn PDF document text
    • http://gkz-crimea.ru/userfiles/file/77884560481.pdfIn PDF document text
    • https://thuaphatlaihanoi.net/uploads/files/sedaluzewosezuvaxu.pdfIn PDF document text
    • http://imbirimbir.ru/files/45031729269.pdfIn PDF document text
    • http://camelliafb.com/uploads/files/202109062355306368.pdfIn PDF document text
    • http://koyomisushi.com/uploads/files/35567181610.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1613b80d296eff---pomujugifitojovupijiro.pdfIn PDF document text
    • https://shivajigrihnirman.com/singhania/downloads/file/jumubefulurujegefodugome.pdfIn PDF document text
    • http://rialta.ie/userfiles/files/xupaxata.pdfIn PDF document text
    • https://mywayrtk.com/userfiles/file/58718669850.pdfIn PDF document text
    • https://pui-vital.ro/msg_media/file/88872274686.pdfIn PDF document text
    • http://orderbestwings.com/uploads/files/38582685168.pdfIn PDF document text
    • https://magerp.org/upload/files/difemebetepose.pdfIn PDF document text
    • http://eaas-journal.org/survey/userfiles/files/64790091201.pdfIn PDF document text
    • http://zssadkowice.pl/pliki/98706012188.pdfIn PDF document text
    • http://www.portaldasfreguesias.com/portugal/vianadocastelo/vianadocastelo/geraz_do_lima_sta_maria/ckeditor/ckfinder/file/luvinisigun.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/tuvalaweda.pdfIn PDF document text
    • https://tradingphrases.net/userfiles/files/66983388816.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613be0518b2b9---94631506504.pdfIn PDF document text
    • http://coimbrasoftware.hu/images/uploads/files/17893957208.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=streaming+film+the+half+of+itPDF 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_off0000d925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD925 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF137 18560 bytes
SHA-256: 4721471ecedabaf9dbd25fc6f8f9e023b8a3cc732e464d5b96c4933990837924
font_02_sfnt_off00012162.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12162 10568 bytes
SHA-256: 5415b49a8d8d10af04c4945e11e90f2952f76467bc670ceffe829492bda1e6b4