Malicious PDF — malware analysis report

Static analysis result for SHA-256 519371fe6db6093b…

MALICIOUS

PDF

71.0 KB Created: 2021-10-03 03:50:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: ca5679a0ca8eb94197abca398c127144 SHA-1: 7e7ffa0658dd83fdf02bd4d44efdb579ef13092f SHA-256: 519371fe6db6093b4db0ff2ea94d4796d26386abf91cc3f15692e60503962975
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm with numerous distinct hosts, suggesting an attempt to direct users to potentially harmful websites. While no scripts were directly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://abpjseah.news-read.com/upload/files/vosuxaxufudovaj.pdf In PDF document text
    • http://sobinco.cz/ckfinder/userfiles/files/xijuxepatururoxeziva.pdfIn PDF document text
    • http://rockpapersun.com/upload_mce_image/file/78961575643.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210924015128311.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/kixosu.pdfIn PDF document text
    • http://eyupsifalibitkiler.com/resimler/files/32651377975.pdfIn PDF document text
    • https://bestrecycledautoparts.net/images_i/file/68950703658.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/34415886200.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/74012138018.pdfIn PDF document text
    • http://www.itidharamshala.in/images/uploads/files/dafexepiganixakisusakage.pdfIn PDF document text
    • http://friulanamarmi.it/images/file/81136929585.pdfIn PDF document text
    • https://mvmdigital.gr/files/files/27690166459.pdfIn PDF document text
    • https://rotitelor.com/contents/files/33043255787.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/farepabusobig.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/86468058554.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/85624123031.pdfIn PDF document text
    • http://mycoapaisyl.com/webimages/files/23195862507.pdfIn PDF document text
    • http://aiaato.com/FileData/ckfinder/files/20210927_A98E66337A6412CD.pdfIn PDF document text
    • http://whatifitspossible.com/ckfinder/userfiles/files/13104501596.pdfIn PDF document text
    • http://ovstav.cz/app/webroot/files/files/zonabamu.pdfIn PDF document text
    • http://cncforginghammer.com/d/files/73377094019.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/90538317178.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/bc6f7ecc6f60d971b30bf5c90d6fd1ca/gakogesilomodaxo.pdfIn PDF document text
    • http://dxqzx.com/ckfinder/userfiles/files/20211003_051432.pdfIn PDF document text
    • https://ebus.myskoolapp.com/FCKeditor/FCKimgUpload/file/21285168743.pdfIn PDF document text
    • http://tribo.kz/userfiles/File/vonutep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+turn+a+chromebook+into+windowsPDF 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_off0000b58e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB58E 15364 bytes
SHA-256: 50c8eb858c313054cd762da99f8e2ce53e709e9eca59769c26f9f1dba7d290f3
font_01_sfnt_off0000dc93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC93 10996 bytes
SHA-256: e5141a12b7b1593ce12b8d7b587b058ee54d0b6b909be5e4ba0abe5dc86e0897
font_02_sfnt_off0000f5f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1