Malicious PDF — malware analysis report

Static analysis result for SHA-256 d55f6f00d81c1bbb…

MALICIOUS

PDF

80.3 KB Created: 2021-09-12 19:55:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 1e8ea373b06396aa3661261791aa03fd SHA-1: 7c026d57037927538ced9c9a5c5aeb79569b11a5 SHA-256: d55f6f00d81c1bbb7d6d83494176e3b2a3ced40a01e2857f35d9bfe7c777fd32
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farms, with several pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://drafthe.ru/uplcv?utm_term=k+means+clustering+on+images PDF link annotation
    • https://amrapalispot.com/userfiles/file/wadukug.pdfIn PDF document text
    • https://nangluongvada.com/uploads/files/70987145271.pdfIn PDF document text
    • http://skulpt.in/admin/uploads/file/nonepixojadol.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/g8vvn02rvfur146040bunhkhk9/lamisakewovamosat.pdfIn PDF document text
    • https://thebottombillion.org/business_school/uploads/file/bezev.pdfIn PDF document text
    • https://rumahbaruku.com/contents/files/7562114643.pdfIn PDF document text
    • https://brakos.it/file/gopodonewenoxenetadifitaf.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/09d1nbhmc69n7vin675msv6odr/45406038640.pdfIn PDF document text
    • https://electroagro.es/pub/files/24559050883.pdfIn PDF document text
    • http://chukguwang.com/files/fckeditor/file/wemunofitak.pdfIn PDF document text
    • http://archiw.bibliotekalesmierz.eu/img/upload/files/34360681481.pdfIn PDF document text
    • http://www.gabrielamaciel.net/images/content/file/sigapaxadimes.pdfIn PDF document text
    • https://semut73.com/contents/files/deserosurut.pdfIn PDF document text
    • https://alutat.com/data/file/30702142793.pdfIn PDF document text
    • http://www.parkwaytransplant.com/media_upload/upload/files/21637354013.pdfIn PDF document text
    • http://herbwaterthailand.com/userfiles/files/gurelunagewe.pdfIn PDF document text
    • http://fishngrill.iorderfoods.com/uploads/files/34196829513.pdfIn PDF document text
    • https://nutritie-metabolism-sanatate.ro/app/webroot/files/userfiles/files/pofevo.pdfIn PDF document text
    • http://alcantara.cz/data/file/widuruminogufoxi.pdfIn PDF document text
    • https://pastelbuilders.com/userfiles/file/79055471285.pdfIn PDF document text
    • http://okna-stv.ru/userfiles/files/lexexebuderijiduripa.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138508107353---46096102694.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/pibebinijesarezeponikasu.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/gudotijajuworavozu.pdfIn PDF document text
    • https://cyklo-wellness-penzion-palice.cz/content/54312466399.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_off0000d35e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD35E 18092 bytes
SHA-256: 99e094be0accb176899826d575f570193e435cea95598526a48015557cc3463d
font_01_sfnt_off00010298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10298 10664 bytes
SHA-256: c84afce10de8a76182d1dcdf2b97247d69938998735ee8da7bb11873eee2ab23
font_02_sfnt_off00011b01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1