Malicious PDF — malware analysis report

Static analysis result for SHA-256 92438843941f7eb2…

MALICIOUS

PDF

82.2 KB Created: 2021-09-22 14:14:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c31d6837b8db04ec1ba3657ccd054d74 SHA-1: 7c42e4b22305ac55b0af97ef54d36e1383256d7d SHA-256: 92438843941f7eb21cca4be6a1a68f49d0ba4f52e8f7d8348752cca083da9855
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document employs a social engineering tactic, specifically a browser extension or update installation lure, to trick the user into executing malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the nature of the lure suggests it would likely lead to the download and execution of a second-stage payload, potentially involving JavaScript exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • 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://efckrakow.pl/userfiles/file/57526081606.pdf
    • http://mdsalon.ru/img/lib/file/97866174597.pdf
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/mizuwolepesivu.pdf
    • https://lmetinternationalschool.in/ckeditor/ckfinder/userfiles/files/jeripesa.pdf
    • http://rothemtour.com/FileData/ckfinder/files/20210920_95E4B431ED383804.pdf
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/k8n5m6lghd3k09r10fie04f05d/fovizifafajub.pdf
    • https://limblength-sldf.com/userfiles/file/70537624462.pdf
    • http://kcntanduc.vn/img_duhoc/files/lasodorizaxamuz.pdf
    • http://gelateriacool.it/userfiles/files/gokakuwikuvinofuxo.pdf
    • https://foodexgida.com/uploads/files/45737209767.pdf
    • http://cka-shiba.com/ckfinder/userfiles/files/nogowobaru.pdf
    • https://economiadecomunion.com/ckfinder/userfiles/files/56078337907.pdf
    • http://sjhrz.com/images/upload/File/rozagusesumefazokulel.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/jum28ldp06ed1cdkno1ve5a4t1/piwifazizeve.pdf
    • http://bertrandetgastineaudesigners.com/userfiles/file/sidosizozurana.pdf
    • http://bearings-home.com/userfiles/file/mavimewizigodafaxixe.pdf
    • https://dewalt-naradi.cz/media/upload/editor/file/dosoguvoxolowo.pdf
    • http://wideanglepackaging.com/ckfinder/userfiles/files/kotibololunewopat.pdf
    • https://emilline.dk/ckfinder/userfiles/files/fowowij.pdf
    • http://shinaval.ru/userfiles/file/popifusesa.pdf
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1614139d1072bf---novirifidanuziwi.pdf
    • http://parkingparts.com/Upfiles/file/kesorewivovujipomowoja.pdf
    • http://darstin.com/userfiles/files/89038566565.pdf
    • http://ternovykh.ru/content/file/zonepabosojomamu.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613686ef0f04c---serededajurufif.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=free+robux+apps+that+work+2020
    • 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_off0000dbb4.bin
b6345246a0de328117755fc6964e26c1afec99fe73ce30ece1de2a4fed9e2ad1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB4 10848 bytes
font_01_sfnt_off0000f4c9.bin
aa27bc870a8d1eaff5398cd5da0a6d46d8ec5733635dba4f13de55d0dc55b492
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C9 17732 bytes
font_02_sfnt_off000122da.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122DA 16792 bytes