Malicious PDF — malware analysis report

Static analysis result for SHA-256 90b3b71adbbc7167…

MALICIOUS

PDF

78.0 KB Created: 2021-09-12 05:19:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1360bebb8845ff0e85e52ec649d3f248 SHA-1: 7e4c7c3114c5e54cec1e03b9afbd338cdc095b75 SHA-256: 90b3b71adbbc716775ad1e9536c93d9acf4d5c654e8461d46a8b685cfb324e5d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised CMS uploads, indicative of a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or SEO manipulation. The embedded JavaScript is likely used to facilitate redirection or further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://ketchas.ru/uplcv?utm_term=how+to+connect+ps4+controller+to+a+phone
    • http://nawooelcs.com/upload/userfiles/2021/09/files/210909035550.pdf
    • http://primeasset.hu/fileok/file/86983675860.pdf
    • https://akapacha.com/userfiles/file/25315797863.pdf
    • http://www.mab-solutions.fr/upload/file/ruzojubavirapolonosaroset.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3dfc24355---60034735249.pdf
    • http://mirutte.com/newsfiles/files/zesovexorezirukuwez.pdf
    • http://omeofest.eu/userfiles/files/23776437299.pdf
    • http://studioboscono.it/userfiles/files/refumonekotu.pdf
    • https://a-metal.e-giant.net/archive/file/files/bosabuporulutageb.pdf
    • https://dichvuhappyhouse.com/upload/files/tofexitu.pdf
    • https://apaman.ti-am.jp/js/ckfinder/userfiles/files/bezonubelarojepesujavaru.pdf
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/2a59577a21741ebde1e402a5e18fdce6/jinanokiba.pdf
    • http://www.chp.pl/ckfinder/userfiles/files/57154572785.pdf
    • http://deleersnijder-bocaege.be/images/file/lokopeluwuxo.pdf
    • http://edallyshop.com/upload/files/pudegabutozuwiboxulowek.pdf
    • http://gt-outillages.fr/ressource/site-image/files/90844488047.pdf
    • http://due.pt/js/ckfinder/userfiles/files/toxomiwefazove.pdf
    • https://ausztriasi.spawellness.hu/upload/hirlevel/files/22822159807.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135960850bdd---56155556606.pdf
    • http://limobebe.com/userfiles/files/nanetilufijokugepebek.pdf
    • http://nuitsdartistes.eu/images/file/dovifufasev.pdf
    • http://kuresi-kaitori.com/upload/content_pic/files/naseviwigi.pdf
    • http://milwaukee.center/userfiles/file/vumalejuge.pdf
    • http://mitsubishilongbien.vn/images/ckeditor/files/90599163287.pdf
    • http://clainvest.pl/userfiles/file/navifofupidufokanewa.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_off0000cbf1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBF1 16792 bytes
font_01_sfnt_off0000e408.bin
d2993f0128f89386cbd2e77ba9143f0fb3bf724989bc9dde3bf9a037d8e2349d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE408 10536 bytes
font_02_sfnt_off0000fc0a.bin
36a551bdab1730f2429afd62a1ed1e20c16c310d70d19064f408db46f1d77575
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC0A 17920 bytes