Malicious PDF — malware analysis report

Static analysis result for SHA-256 772d73ffbc5fca35…

MALICIOUS

PDF

83.2 KB Created: 2021-09-18 12:11:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b4d1e60606d110bd954070459274053b SHA-1: 5c2e819ff51f383434414081cae8dc1a7f1f4213 SHA-256: 772d73ffbc5fca35408f7ef6c5e6d7116d51fa9f517c0b087f17822f4a77d609
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains embedded JavaScript, which is often used to exploit PDF reader vulnerabilities or redirect users. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates the document is a link farm on disposable hosting, and numerous external URLs were extracted, reinforcing the phishing or malware distribution lure. The embedded JavaScript likely attempts to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://allytemp.ru/uplcv?utm_term=sony+android+jelly+bean PDF link annotation
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/59690376d83399c8496628f10f2ef244/1207552926.pdfIn PDF document text
    • http://eraldocomo.it/userfiles/files/jowazoruwe.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/tekini.pdfIn PDF document text
    • https://resonanceacteurs.nl/userfiles/file/36890076588.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/53082377065.pdfIn PDF document text
    • https://tumsad.org/img/editor/image/file/lesuvadoposebo.pdfIn PDF document text
    • http://stelmart.ru/userfiles/file/retobod.pdfIn PDF document text
    • http://mosvag.ru/img/lib/file/26364142669.pdfIn PDF document text
    • http://hotelalbicia.com/userfiles/file/23447254445.pdfIn PDF document text
    • http://abwingsbuffalo.com/uploads/files/melugewunarotun.pdfIn PDF document text
    • http://togul.org/sites/default/files/file/68424084265.pdfIn PDF document text
    • http://www.iece.in/userfiles/file/12099661439.pdfIn PDF document text
    • http://lidaoxc.com/upload/files/80762888642.pdfIn PDF document text
    • http://tobn56.com/UpFiles/file/17570413075.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/vowikatatorabikufow.pdfIn PDF document text
    • https://sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/69263878249.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/78923138778.pdfIn PDF document text
    • http://cachnhietwin.com/luutru/files/40420839713.pdfIn PDF document text
    • https://mtydizayn.com/userfiles/file/sumotepuzazetemosevu.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c8aee85146---59709714501.pdfIn PDF document text
    • http://soupworld.de/upload/file/68666095876.pdfIn PDF document text
    • http://s2group.pl/userfiles/file/tusabaposaxonugo.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/73537465413.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1614366b00d5bc---jokew.pdfIn PDF document text
    • http://vnationwide.com/userfiles/files/jevukulinosasonopolaja.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_off0000d9ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9ED 10436 bytes
SHA-256: 3edad02743ab4d7857e28cd2d150fba31a83b9cb12d569764399a6e4437a1e27
font_01_sfnt_off0000f19c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF19C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109AE 19952 bytes
SHA-256: 5fed9e7cb2157bafb1fa13c21bdf3aa5908ce8106847c70d83563c0f064c17cc