Malicious PDF — malware analysis report

Static analysis result for SHA-256 8561f34c3cdf0237…

MALICIOUS

PDF

71.3 KB Created: 2021-09-30 15:05:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 6c137a53b02f39a4caa85bab505784d0 SHA-1: a0988333371195bc9e848a2abce5adef8e3cc740 SHA-256: 8561f34c3cdf023732cda59ed55e26082fca4949edb4f333dae813770bfcd4b9
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable domains, characteristic of a link farm designed to distribute malicious content or phish for credentials. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://bbbo.handyfriendship.com/upload/files/berufomuguvudukevizige.pdf In PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161458ab686896---godabusiluzom.pdfIn PDF document text
    • https://andhimazhai.com/images/files/17793112210.pdfIn PDF document text
    • https://biographiewerkstatt-singer.de/userfiles/file/94525311868.pdfIn PDF document text
    • https://bartonsteel.com/tony/barton/ckfinder/userfiles/files/gunamixuzozifigu.pdfIn PDF document text
    • http://flyingfish-stay.com/userfiles/file/wuzeve.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/rupowuwugakovoxe.pdfIn PDF document text
    • https://apc-algercentre.dz/ckfinder/userfiles/files/misezokizunatelazopopo.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/renexiwapusukin.pdfIn PDF document text
    • https://gamaconsultores.cl/upload/file/denuragupanovanidepiwi.pdfIn PDF document text
    • https://begili.com/uploads/image/files/38665724760.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109191826249308.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/09d8907460827e05a5c7ac7867cee18b/sojogeguduxanepirujegem.pdfIn PDF document text
    • https://laznia-radom.pl/userfiles/file/6669605953.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/zatolowoloxur.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad0ac35b41---87776556502.pdfIn PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/39304678311.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/gukunimipaxarodek.pdfIn PDF document text
    • http://tchid.net/userfiles/file/90727933717.pdfIn PDF document text
    • https://hankilfood.com/upfile/files/53610986256.pdfIn PDF document text
    • http://naphogacomposite.com/upload/files/nilafodefexuf.pdfIn PDF document text
    • https://www.burnat-provins.ch/ck/ckfinder/userfiles/files/jozizeratudalebi.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/65104563618.pdfIn PDF document text
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/95994385766.pdfIn PDF document text
    • http://turbotechnik24.de/userfiles/file/9305570829.pdfIn PDF document text
    • https://nodka.eu/ckeditor/ckfinder/userfiles/files/tusumeta.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=diagram+of+the+heart+labeled+simplePDF 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_off0000b3c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3C9 16668 bytes
SHA-256: e134e7de4278dda92379cdc2c510128f293e70d1d99e84be7d9f71164e0986de
font_01_sfnt_off0000de67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE67 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f67e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF67E 10984 bytes
SHA-256: 1acdcea59c784d1731c89190c1f69686b0423b82b1ce1eb2b62405b7fd30732a