Malicious PDF — malware analysis report

Static analysis result for SHA-256 f28aa5cb1acc7437…

MALICIOUS

PDF

82.9 KB Created: 2021-09-20 18:46:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 823833414f5f2e44b2d1ba9321afec48 SHA-1: 29499b6b718d4da1deb19844a3af4ae841e42311 SHA-256: f28aa5cb1acc74374d0c0f2022042e8f48168cd6878735d390b1aaaa232659fc
166 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous URLs pointing to disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of 'cmd.com' in the document text, along with the PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics, strongly suggests an attempt to exploit vulnerabilities or trick users into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://laborke.ru/uplcv?utm_term=ldplayer+4+download+for+pc+windows+10 PDF link annotation
    • https://altonika.pro/files/fck/file/5959755571.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/voridejisula.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140ec1c92d8e---tuvagef.pdfIn PDF document text
    • http://eviljoy.com/UserFiles/File/dojezolalegifekafofa.pdfIn PDF document text
    • https://qfuse.it/images/uploaded_files/ckfinder/files/1630730214_9ed3847d63.pdfIn PDF document text
    • http://letsbelegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/53218552348.pdfIn PDF document text
    • https://aicpwdosaeast.com/ckfinder/userfiles/files/fusemujigosujipu.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/zuzobarinulatojisemevi.pdfIn PDF document text
    • http://korsorlampang.net/user_img/files/30553114855.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/24116566623.pdfIn PDF document text
    • http://sosonomo.com/ckfinder/userfiles/files/51400384450.pdfIn PDF document text
    • http://www.77ice.com/upload/files/lobirumezixewalurilixiru.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/3onpc8uef49inmsfuf9asgao9i/3826039581.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/10108514906.pdfIn PDF document text
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/78833591926.pdfIn PDF document text
    • https://breedlife.com/upload/files/94828365735.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/75808751882.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/mowevukofodosidizasi.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/zuvizebuwimowizuti.pdfIn PDF document text
    • http://i-physiology.ru/upload/42101891895.pdfIn PDF document text
    • http://fra2ange.it/userfiles/files/50626646255.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/9771212349.pdfIn PDF document text
    • http://qdcmd.com/data/files/8210232945.pdfIn PDF document text
    • https://senfina.top/uploads/files/pivaj.pdfIn PDF document text
    • http://elezioni2014.gds.it/userfiles/file/91197615839.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_off0000def5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF5 17564 bytes
SHA-256: 3e371eb8732bdddeaa1eeff2a037868968e2610f3f5cfb6bf1f2ecffee87c039
font_01_sfnt_off00010c47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001245e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1245E 10924 bytes
SHA-256: bb67e4741579ca252719c541784d7ad6c2e34b3e520c726e02e77c98157ddea1