Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef9ed28f4cad91fe…

MALICIOUS

PDF

82.8 KB Created: 2021-09-12 07:33:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6b25c4c3b4b922500dce20e116744400 SHA-1: 5432bcb9ba37e947aa0e3530b76177ab8156d2f7 SHA-256: ef9ed28f4cad91fe4d1e010d12b0cc856508fe3409e9fe09f1275649ae088b37
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing embedded JavaScript and a large number of external links, 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 a common technique for exploiting PDF vulnerabilities or initiating malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://cructi.ru/uplcv?utm_term=how+to+connect+xbox+one+controller+to+firestick PDF link annotation
    • http://obkladlazby.cz/userfiles/file/devamusevizosivejuxozube.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/nibefizitimufirinujumezi.pdfIn PDF document text
    • http://www.artefuoricentro.it/js/lib/ckfinder/userfiles/files/zalezenavuwuvegomarig.pdfIn PDF document text
    • https://dd-inside.de/userfile/file/52873498081.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/sekal.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/zazejuvelagapunired.pdfIn PDF document text
    • https://itandem.net/ckfinder/userfiles/files/tivavaxifage.pdfIn PDF document text
    • http://imbirimbir.ru/files/fiwebidesomuvakavajez.pdfIn PDF document text
    • https://shen-su.eu/gfx/userfiles/files/87833511172.pdfIn PDF document text
    • http://skisun.it/userfiles/files/pufugigubawo.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/20317566493.pdfIn PDF document text
    • http://email-database.info/userfiles/file/tunagogabivilonora.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/delapupe.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/q0qoknjbas5lef93tprpsu8vn1/kalenoniwixoraginiliber.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/10283096526.pdfIn PDF document text
    • https://socardan.com/userfiles/files/rotibetudat.pdfIn PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/32863423013.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131ab8a8fc67---89205656934.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/94484819847.pdfIn PDF document text
    • https://ku4ysk-9lgp4y.com/contents/files/81627634466.pdfIn PDF document text
    • http://shahnawazonline.com/uploads/files/pilet.pdfIn PDF document text
    • http://cuanhuadanang.vn/uploads/image/files/34695027337.pdfIn PDF document text
    • http://elcolono.net/userfiles/files/jiketefitu.pdfIn PDF document text
    • http://quimis.org/js/ckfinder/userfiles/files/3847678443.pdfIn PDF document text
    • https://10playsolutions.com/clients/softklk/documents/_articles_/file/sewuxorutumilopukeximu.pdfIn PDF document text
    • http://vestmorecapital.com/images/epost/forapev.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_off0000dce9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCE9 18336 bytes
SHA-256: e56fc2eccdf64e813701f865e70d784e375050dde5d40745fe9c79937988eaef
font_01_sfnt_off00010c9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000124b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124B4 10576 bytes
SHA-256: 51fda74cf07a84a72e3d994c5df5e3e0040d51d18f2860132724cba2c32f7779