Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bf2a7df6e114d16…

MALICIOUS

PDF

88.7 KB Created: 2021-09-13 02:28:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a038553d57d1e88466bce74cba5824cb SHA-1: bbd92c1a2550fb9931037c240a77067437ed8ed7 SHA-256: 3bf2a7df6e114d16149bdb7d5dc021acb9a2e06ebaff280b03499d41604b112f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, a common tactic for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or serving a malicious payload. Although no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://synerhu.ru/uplcv?utm_term=linux+kernel+development+4th+pdf PDF link annotation
    • https://easresidence.ro/app/webroot/files/userfiles/files/vurejegudov.pdfIn PDF document text
    • http://geodavidepini.it/userfiles/files/74879072792.pdfIn PDF document text
    • http://ordineveterinarireggioemilia.it/userfiles/files/58840688983.pdfIn PDF document text
    • http://auburn-companies.com/userfiles/files/26869357848.pdfIn PDF document text
    • http://niktid.ru/userfiles/file/20050452987.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/suveropabipuwarokinere.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-9-11/20210911061417913886.pdfIn PDF document text
    • http://ateliergermain.club/sites/default/files/file/91057515621.pdfIn PDF document text
    • http://katela.net/userData/board/file/70651593231.pdfIn PDF document text
    • http://cmtoolsrental.com/user_img/files/dabubiwoxome.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3f63410c0---dotujawufefowotowojaje.pdfIn PDF document text
    • https://coherence.cz/userfiles/file/31238413575.pdfIn PDF document text
    • https://holcom-solar.com/webroot/img/files/lizegusop.pdfIn PDF document text
    • https://webrobogo.hu/kepek/40006372514.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/22287773363.pdfIn PDF document text
    • http://kor-ra.ru/UserFiles/file/vufixoruxukawoxuzogisu.pdfIn PDF document text
    • http://kolbiko.com/images/uploads/file/80432902914.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/161395d0e4d7da---80901839012.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/vinudodujudefises.pdfIn PDF document text
    • http://kevinmcallisterlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/duvozoxa.pdfIn PDF document text
    • http://xn--80aaa1acmiejxr6d7fg.xn--p1ai/data/files/7515175827.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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d08b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD08B 19732 bytes
SHA-256: a9614dab10e4aabddefb0381c8180b2176275f5db045a69a82b25e20dfeb3f27
font_01_sfnt_off00010328.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10328 1872 bytes
SHA-256: 529f3d931c6040c484eb5e2568de436a6b2430e26bc62e38864ed55ef75c241b
font_02_sfnt_off00010be3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE3 10828 bytes
SHA-256: 1b1b7610b243080971b86c636f8a1bcfe73364c4ae8a3e783495bca40ef99417
font_03_sfnt_off000124a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_04_sfnt_off00013cb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CB4 16800 bytes
SHA-256: cbc8ec4c3b72610449b203cfc4d041f33f0f10c987dc8faa87311a6abdd31442