Malicious PDF — malware analysis report

Static analysis result for SHA-256 a52b96d25970c869…

MALICIOUS

PDF

71.6 KB Created: 2021-09-14 10:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0fe8787d8a8a684dad414ad6a0d0180c SHA-1: 34884aad6795871cba0362108ee10da21b20850c SHA-256: a52b96d25970c869549a1db4657d03ac497908c12fb1016d9098336a739f29d3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs, many pointing to disposable or unknown domains, suggesting a link farm or phishing lure. The PDF structure itself is also suspicious, with duplicate object bodies, and the authoring application 'wkhtmltopdf' is sometimes used to generate malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/i9g5tuqvjh3onrkqp6dguf7lqm/vefaxirinazilogawox.pdf In PDF document text
    • https://khabul.mn/mmpa/userfiles/files/76094302952.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/81747430992.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/11008414958.pdfIn PDF document text
    • http://www.moyekolodin.com/files/mobiwewonutulu.pdfIn PDF document text
    • https://derya.afmiletisimajansi.info/resimler/files/vudugijuligiwedabewod.pdfIn PDF document text
    • http://ancient-theater.gr/media/file/pivowikowovow.pdfIn PDF document text
    • http://scandinavia-ex.com/images/blog/file/rijekorepot.pdfIn PDF document text
    • https://pharma-tools.eu/galeria/file/32969713711.pdfIn PDF document text
    • http://xn--3bsx3iw22bmot.com/filespath/files/20210906213816.pdfIn PDF document text
    • http://coffee33.ru/archive/file/varuza.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/musigodexufisuxukumas.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/jekepa.pdfIn PDF document text
    • https://beysukonaklari.com/ckfinder/userfiles/files/foxedonuda.pdfIn PDF document text
    • http://dgjinhak.kr/DATA/upload/files/202109050850108510.pdfIn PDF document text
    • http://e-menu.hu/editor_up/zesasivitutijojuxo.pdfIn PDF document text
    • http://eltdb.com/UserFiles/files/5028727652.pdfIn PDF document text
    • https://otoform.com/upload/ckfinder/files/95758162346.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/vebixadarumuledevagukozev.pdfIn PDF document text
    • http://hillcrestneighborhoods.com/userimages/14590026123.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/3bfef82133a70db0d8881bf58f260882/dilulunu.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/29849998948.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/55789034733.pdfIn PDF document text
    • https://netwindowvn.com/uploads/userfiles/file/33360538070.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=rte+player+android+tvPDF 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_off0000b56b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB56B 17060 bytes
SHA-256: 2b3c8429ff352f99904f88bc73ac0f4fb28bf245a504b3d8178e732604aa366d
font_01_sfnt_off0000e12b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12B 10440 bytes
SHA-256: c4b076026481b27079ea7348d16729c30441177d2db958f130c34cd4f6dd19b2
font_02_sfnt_off0000f8fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1