Malicious PDF — malware analysis report

Static analysis result for SHA-256 93144366aad83820…

MALICIOUS

PDF

80.4 KB Created: 2021-10-10 18:50:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 451a6bb7f7c8bbe43a46b295428d9a6c SHA-1: 19d812fbd407ee5d5677cfe20e40b50501b2fe31 SHA-256: 93144366aad83820a38ed84568a077d812976c68aceb7662307c80bcbfae7e1c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate it functions as a link farm, directing users to numerous external URLs, one of which is `https://smidgel.ru/uplcv?utm_term=ayzha+nyree+no+guidance+download`. The PDF structure and embedded links suggest it is used as a lure, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://smidgel.ru/uplcv?utm_term=ayzha+nyree+no+guidance+download PDF link annotation
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130e95c92359---nuwusidomabeze.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1615e82197dbf4---12731648687.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/kowinimadurajoxa.pdfIn PDF document text
    • http://elard-group.com/ckfinder/userfiles/files/80497746680.pdfIn PDF document text
    • https://whiteplacard.com/UserFiles/file/dakunezude.pdfIn PDF document text
    • http://dailygiasi.com/uploads/userfiles/file/54665402986.pdfIn PDF document text
    • https://gruppopolidori.com/upload/image/file/kusifigi.pdfIn PDF document text
    • http://smolninskayahotel.com/userfiles/file/bifojur.pdfIn PDF document text
    • https://mariapolis.es/ckfinder/userfiles/files/betugume.pdfIn PDF document text
    • http://thephinhmienbac.com/upload/files/mobewodetirivakiram.pdfIn PDF document text
    • https://ceiling.holcom.vn/webroot/img/files/wisoxutaju.pdfIn PDF document text
    • https://beamstraffic.com/amb/userfiles/file/julugipoxawu.pdfIn PDF document text
    • https://behbehaniprojects.com/uploads/files/54359720923.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/vosixutenebulajegadisoga.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/99763754380.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/11463163686.pdfIn PDF document text
    • http://aotwresort.info/ckfinder/userfiles/files/74203321194.pdfIn PDF document text
    • https://bimstudioinc.com/media/files/wujivigujidefiro.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/mesadijobezap.pdfIn PDF document text
    • http://ganteltechnology.com/system/userfiles/file/fatevuxas.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109030053027567.pdfIn PDF document text
    • http://cafecontinentalmd.com/uploads/files/35635782576.pdfIn PDF document text
    • http://dajuicebarus.com/uploads/files/24138029278.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_off0000c8be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8BE 21900 bytes
SHA-256: 4a0c075d4d93cfe9893dc76387298408a2d86f9f9d6779ed38d49ddb945bb6a1
font_01_sfnt_off0001021b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1021B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A32 10724 bytes
SHA-256: 8b266c3f39a63ac0cc4030d4ae8f66b826c4115a8bcb8acb61331da225534160