Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a987c22b3410323…

MALICIOUS

PDF

75.0 KB Created: 2021-09-15 21:44:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 08c868f09ad9c9ee4ac0755c7d6275bc SHA-1: 3a7b2c80067f823e31767f490a906ee14a264ba9 SHA-256: 5a987c22b3410323459f57642bf3ea4b6413db34d1d3ef61a2d0b93f4d88488c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which are structured as link farms, suggesting a phishing or malware distribution attempt. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the ClamAV detection 'Pdf.Phishing.Trojan-d2568dad23a94d95-10044375-0' strongly indicate malicious intent. The presence of external URIs like 'https://chcial.ru/uplcv?utm_term=free+download+gta+san+andreas+highly+compressed+for+android' further supports this, likely serving as a lure for users seeking software downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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.
  • 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://chcial.ru/uplcv?utm_term=free+download+gta+san+andreas+highly+compressed+for+android PDF link annotation
    • http://dongduong.net/Images_upload/files/85051968143.pdfIn PDF document text
    • http://skupka54.ru/upload/m/noredexezekijokotepal.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/44029599966.pdfIn PDF document text
    • http://turhantur.com/turhantur/files/jowifivalixufinar.pdfIn PDF document text
    • http://s-privod.ru/userfiles/file/mobosewojirerav.pdfIn PDF document text
    • https://dailyiat.com/html_upload/file/papozanakisev.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/53866063574.pdfIn PDF document text
    • https://www.babetravelling.com/ckfinder/userfiles2/files/55538620496.pdfIn PDF document text
    • http://www.macrolepidoptera.hu/userfiles/files/16635901850.pdfIn PDF document text
    • http://www.thaitofu.com/image/upload/File/bogisedipatox.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/niwumaxugafarobumexilek.pdfIn PDF document text
    • http://myslizdrave.com/soubory/18870542398.pdfIn PDF document text
    • https://ptogel2.com/contents/files/18752641679.pdfIn PDF document text
    • http://nikacarpet.com/My_Project/Hamishe_bahar/ahar_img/files/9667823403.pdfIn PDF document text
    • https://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/dobutukof.pdfIn PDF document text
    • http://wangyiphk.com/userfiles/waverisonujolum.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/32039116203.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/161364952e3bca---20237222352.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612f016be1d3f---xarilufa.pdfIn PDF document text
    • https://galerie-louise.be/userfiles/files/busovitusipa.pdfIn PDF document text
    • http://byecook.com/ckupload/files/62644699381.pdfIn PDF document text
    • http://debten.net/UserFiles/File/37015160551.pdfIn PDF document text
    • http://solemarservizi.it/userfiles/files/58278729282.pdfIn PDF document text
    • http://gearcon-eng.com/file_media/file_image/file/94503390429.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_off0000c146.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC146 11244 bytes
SHA-256: ca3483095437026714a4e18a30908594329f5edfe60d6cd8bfc5a397d16632aa
font_01_sfnt_off0000db50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB50 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f362.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF362 16540 bytes
SHA-256: 1fb7d807acbd18c98fe2106a23b23a19397b1cecb67b868f9d2b8051477c1750