Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab4fd09fadc978af…

MALICIOUS

PDF

84.0 KB Created: 2021-09-16 07:35:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 41540e79f8716691f05ce25f340726d6 SHA-1: 61b01ac653bba41db8516629815397071d0dc642 SHA-256: ab4fd09fadc978af9805c96e05e215ac84e2d2d31e26027b4dbb7be723fefb3a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised WordPress sites or disposable domains. These links likely lead to phishing pages or malware downloads, consistent with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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=444+repeating+numbers PDF link annotation
    • https://at2-turbo-j3t.com/contents/files/bajozovalavufeja.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/3086040029.pdfIn PDF document text
    • http://flexicourse.cz/res/file/81982725343.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/dndl1j62qjb85q8nob0rfr15o4/44008323069.pdfIn PDF document text
    • http://ceskylakros.cz/userfiles/file/rugosumutexukozoxe.pdfIn PDF document text
    • http://laboratorioshamalab.com/userfiles/file/84311116461.pdfIn PDF document text
    • http://napiarsaigh.com/images/voralin.pdfIn PDF document text
    • http://mevlanaasm.com/resimler/files/75668026039.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/n1d38c19nc2ececvnhbktm6bao/67750501853.pdfIn PDF document text
    • http://englandmatchshirts.com/assets/file/65369257061.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9ec2e2ef6---jovasupekoregowuxa.pdfIn PDF document text
    • http://compufoxmail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/84812768771.pdfIn PDF document text
    • http://montex.pro/uploads/userfiles/file/xulowi.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/93702746126.pdfIn PDF document text
    • https://braus.uz/images/shared/file/poduwivan.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/38584148055.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/40028313005.pdfIn PDF document text
    • http://familiegravesen.dk/ckfinder/userfiles/files/18248921675.pdfIn PDF document text
    • http://autoscuolauniversale.it/userfiles/files/bitiriborumakatewifuxo.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/gosisedare.pdfIn PDF document text
    • http://chingyi.tw/userfiles/files/pesaruludegukunoruridoxel.pdfIn PDF document text
    • http://waetsukai.jp/system/ckfinder/userfiles/files/65213762505.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/47332102a30367fa603e40e2db64cb16/xijogiwulowager.pdfIn PDF document text
    • http://xn--80aafbanafwvcftiqfecrg2a.xn--p1ai/pict/file/fuwavevivomolire.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613062cf9df26---fijez.pdfIn PDF document text
    • http://interiorconsignments.com/media/file/18374621764.pdfIn PDF document text
    • http://elpijisystem.com/file/jinapusago.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_off0000e50f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE50F 17596 bytes
SHA-256: 1c6c3046e92b361a7be1a572a68238e6e9542919d7cb98c5835440efde6efcae
font_01_sfnt_off00011265.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11265 10648 bytes
SHA-256: 00dd9317716cf8e321530cec75356373814918af0a49b7234d0a3205d9827155
font_02_sfnt_off00012a90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1