Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d4b1d06cb156ad0…

MALICIOUS

PDF

86.8 KB Created: 2021-09-18 21:23:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b57d7db6eaa20aedfa40ee3a8afe75d2 SHA-1: e12ee88e8636d3562169be34d0d72899e46fcff0 SHA-256: 4d4b1d06cb156ad0133cc1655dd2dfac4318d9801712186cf1f12df174aa3973
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to lure users to potentially malicious destinations. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The file's structure and URL patterns are consistent with a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://queure.ru/uplcv?utm_term=adding+and+subtracting+similar+fractions+worksheets PDF link annotation
    • https://inverpalmas.com/aym_image/files/34881660095.pdfIn PDF document text
    • https://atasuorganiktarim.com/upload/ckfinder/files/39279791952.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161350869af5b6---13663403954.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec2a6c2b20---zuxinigugadanositagomika.pdfIn PDF document text
    • http://opusincertum.it/userfiles/files/16831918105.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/kaponerif.pdfIn PDF document text
    • http://praconsulgroup.ru/pict/file/18663467219.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/240626028.pdfIn PDF document text
    • http://turchifiltri.com/userfiles/files/51990040166.pdfIn PDF document text
    • http://azizolace.cz/images/file/55948006553.pdfIn PDF document text
    • http://xn--80aer5aza.xn----htbdepbihnfb8cyg.xn--p1ai/ckfinder/userfiles/files/91027136509.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f15e8b04d8---gaxegafagixesavafa.pdfIn PDF document text
    • http://www.wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/gomadirulizinuzolo.pdfIn PDF document text
    • http://abnicum.ru/files/file/95692969518.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/sevadotalibigeta.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131c8782e75b---98243969412.pdfIn PDF document text
    • https://robustbrakes.com/administrator/imagetemp/file/nijirisaxosodugobalu.pdfIn PDF document text
    • http://riverla.vn/uploads/userfiles/file/14069552047.pdfIn PDF document text
    • https://art-eria.pl/mandarynka/pliki/files/mugajilodazigawujibewe.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/43117452118.pdfIn PDF document text
    • https://netpage.info/userfiles/file/dijejomixuduliwalixi.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/xotonerib.pdfIn PDF document text
    • https://rossbeede.com/userfiles/file/93522388579.pdfIn PDF document text
    • http://pallenberg-busreisen.de/uploads/files/rokikabazir.pdfIn PDF document text
    • http://asid.rw/userfiles/file/jexupirogezizageviruluk.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_off0000eac7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC7 11324 bytes
SHA-256: dcd727daa84aa23b69900692de6ea37e3fe8a8d2accf00b1dae7d855a7a92771
font_01_sfnt_off00010522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10522 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D34 18316 bytes
SHA-256: b5834910d1e5aa309a2ea1b01b7d67efc1b13c41d57a0a50e9cd604242d2066a