Malicious PDF — malware analysis report

Static analysis result for SHA-256 70853163fe3cda5a…

MALICIOUS

PDF

68.4 KB Created: 2021-09-28 13:14:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4ca6b67645f9f25ae5621d3916ae423d SHA-1: e33041d7a81a9168d4f29de40d12cc450a046e71 SHA-256: 70853163fe3cda5a6a7aad3dfc35424980a3a96ebcdb33713d083d5e4615e356
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://inwebjor.ru/uplcv?utm_term=trainz+driver+apk+data
    • http://omonetach.pl/foto/ilustracje/file/zogipal.pdf
    • https://perfecthospital.org/ckfinder/userfiles/files/fabiguwusedagumijux.pdf
    • http://saigonford3s.com/uploads/2021-09-23/images/files/kivakonesetorisawibijelub.pdf
    • https://stvietnam.net/luutru/files/4489950803.pdf
    • https://sunsetlearningcenter.com/userfiles/file/79902116375.pdf
    • http://trungtamdaykem.vn/Images_upload/files/31945882683.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161507fffb6964---26215402492.pdf
    • http://gddfboiler.com/uploads/files/34479570177.pdf
    • http://hz-kontejnery.cz/ckfinder/userfiles/files/24924031042.pdf
    • http://stylekd.ru/files/5800958358.pdf
    • http://anpo.vn/upload/files/xevigixur.pdf
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16143c56f64a52---bilarataxawegifil.pdf
    • https://catwalkdogcome.com/editor_upload_image/file/38111559728.pdf
    • https://sakkestadbil.no/userfiles/file/2964985338.pdf
    • https://vico-inmobiliaria.com/ckfinder/userfiles/files/godezeriduruvebolufij.pdf
    • http://awarelaxcentrum.cz/user_files/file/21005714868.pdf
    • https://xistenze.nagydavid.com/files/files/pusotexomupadivine.pdf
    • https://successstudio.net/userfiles/file/romenakagatapixilufogor.pdf
    • http://paintmaster.hu/js/ckfinder/userfiles/files/lebaloguv.pdf
    • http://boschvietnam.com/files/usersfiles/files/12986360900.pdf
    • http://hoteldanang.vn/uploads/images/files/rikugevozekosatokiwivir.pdf
    • http://sbairs.com/datas/files/11721413607.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b072.bin
21f4fbe1dd49251a86d443ebc3fb0a3a7a9ef8e0a89105def9fa326321acfa53
pdf-font-stream PDF embedded font (sfnt) at offset 0xB072 14368 bytes
font_01_sfnt_off0000d4c8.bin
a66a4f6b33e1915c45f97fa4daf15fa08a5a615b6b727183e023437c49f06eec
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C8 10232 bytes
font_02_sfnt_off0000ebe5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBE5 16792 bytes