Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b631474392a94be…

MALICIOUS

PDF

80.3 KB Created: 2021-09-13 16:42:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8791ce44115337398ff024403d5223b6 SHA-1: 81302490f7a0395bf9f1d98f7b695a8d8fa5e296 SHA-256: 1b631474392a94bee723fb257198fc3063eda66f2c184dd8c954fb8994905568
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to unknown PDF files hosted on various domains, some of which appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. No scripts were extracted, but the structure and URL patterns suggest a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/a6d5341666ba9efe6e9e632f8f583b76/zovisudedajiboroz.pdf In PDF document text
    • http://maekalocal.com/Maeka/UserFiles/File/50887917375.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/redemifurunabawizo.pdfIn PDF document text
    • https://xn--49st2et51duvk.com/upload/files/41157905130.pdfIn PDF document text
    • http://musiclivemarsala.com/userfiles/files/temimonavulazepezolalogol.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/lepep.pdfIn PDF document text
    • http://360global.ca/userfiles/file/nosovofowozaxanasak.pdfIn PDF document text
    • http://simp-q.ru/userfiles/file/fodijivemedixefanefav.pdfIn PDF document text
    • https://exihomes.com/userfiles/files/puvuwewaviludup.pdfIn PDF document text
    • http://itaxabc.com/userfiles/file/20210913191938_546559490.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/75381648905.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/numazifotob.pdfIn PDF document text
    • http://elateridae.com/images/FCKeditor/file/bagupeburajoxomexaja.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161382604411c9---molazezitusijudux.pdfIn PDF document text
    • http://marienoellebermond.com/img/uploaded/file/bikikakilegamedugebiti.pdfIn PDF document text
    • https://mandarinusa.com/userfiles/file/1630469241.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/wisad.pdfIn PDF document text
    • https://pharmawell.eu/ckfinder/userfiles/files/57231726942.pdfIn PDF document text
    • https://sogelec-eng.com/files/ckfinder/files/rixofotinivori.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/43080b86982f54729722ad3e99c62a18/lazumapibumerij.pdfIn PDF document text
    • http://taihegas.com/filespath/files/20210908223202.pdfIn PDF document text
    • http://cuanhuadanang.vn/uploads/image/files/botater.pdfIn PDF document text
    • http://eng.sut.ac.th/tce/2016/administrator/ckfinder/userfiles/files/45754954484.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=clash+of+clans+hack+app+unlimited+gemsPDF link annotation
    • 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_off0000d4e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4E0 17332 bytes
SHA-256: 33c828284de160c3439072d87fcd304ee563d25babaaf75ee8d5630b81a626a2
font_01_sfnt_off000101c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C0 11192 bytes
SHA-256: 6c647d65c0fffe2f3c5be5c020e3aec646689ca3665dcfef880638aca8a6da22
font_02_sfnt_off00011b8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1