Malicious PDF — malware analysis report

Static analysis result for SHA-256 27f0b99b7cf39a53…

MALICIOUS

PDF

89.7 KB Created: 2021-09-11 23:18:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a79764973296893fc34bfb33f59d4af2 SHA-1: e5d5b584288f263cdfdfdebaa047f9106c18f6e2 SHA-256: 27f0b99b7cf39a53135e3316bf7d6c335c766cd935dd8a4ad9c84a4dcd9df53c
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to a variety of domains, many of which appear to be compromised or disposable hosting. Heuristics indicate this is a link farm designed to direct users to external content, consistent with phishing or malware delivery. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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://crysiq.ru/uplcv?utm_term=how+to+make+purple+paint+brighter PDF link annotation
    • http://bluebossa.pl/files/file/37270971058.pdfIn PDF document text
    • http://njuhome.pl/ckfinder/userfiles/files/57182121423.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/lavejirozumitupefiloj.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135e08e4b2e4---55586144436.pdfIn PDF document text
    • http://safeabortionnepal.com/userfiles/file/62830845047.pdfIn PDF document text
    • http://hanahana.vn/media/ftp/file/jakezumaladusiduxel.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16136328176bdf---48805929579.pdfIn PDF document text
    • http://tao-oita.com/admin/upload_filesfile/kajaduneroravezugemab.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/79299644675.pdfIn PDF document text
    • http://bebaldebaran.eu/userfiles/files/danom.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613a896f07f87---wozozimiti.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/zisigejumolufuvazaga.pdfIn PDF document text
    • http://www.ezmoving.com/file/46617392004.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/zogegexogo.pdfIn PDF document text
    • http://packagingandfoodmachinary.com/userfiles/file/wipudi.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/4869200655.pdfIn PDF document text
    • http://igigeothermal.jp/userfiles/file/mosanexasizonunov.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/81540149765.pdfIn PDF document text
    • http://joyearland.com/ckfinder/userfiles/files/44728957035.pdfIn PDF document text
    • https://wupaojichangjia.com/d/files/26538353120.pdfIn PDF document text
    • https://tonerihned.cz/userfiles/file/zoxawidodekanokowitat.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/92679706847.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_off0000f924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF924 10940 bytes
SHA-256: aa7cd3b14698bae7a74004e544272940108fce72bebc8253979298b0513b8a90
font_01_sfnt_off00011200.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11200 18236 bytes
SHA-256: 2c0239f2a87b66857e0d9488e5ddd1c60f591880d1406917fbded5754f7a1405
font_02_sfnt_off00014143.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14143 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1