Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b81d7e272058423…

MALICIOUS

PDF

87.6 KB Created: 2021-07-27 08:50:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3fa5e805c95cc57f488ea2e62319d96e SHA-1: 98d74571633af29567d4c1b9e60f1ad29e2648a7 SHA-256: 0b81d7e272058423346ba31294abdd95010621b053eb75d3387953ba3e28623d
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to external websites hosted on compromised CMS platforms or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm and compromised hosting suggests an attempt to obscure the true destination and leverage potentially untrustworthy infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://my-natural-style.net/upload/files/kedut.pdf In PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/vqfia2pnlai4quducpkes5qabh/kononow.pdfIn PDF document text
    • https://sporyolu.com/resimler/files/mumela.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/besavotiko.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/kefapuxifalakimetuziva.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ff4c244f0---53468189003.pdfIn PDF document text
    • https://west-holding.com/userfiles/file/rupetakuzixopabe.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/91134611203.pdfIn PDF document text
    • http://email-database.info/userfiles/file/vafajezaseduzifarinarabev.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/5446093137.pdfIn PDF document text
    • http://drtamerturan.com/file/4807049187.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160754d0d2b031---24613761976.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/n9f0ass0bj1j0a2j5fk6k4vqq0/gikopafigame.pdfIn PDF document text
    • http://cybernet.asia/UserFiles/File/78007167979.pdfIn PDF document text
    • http://tandprotheses.com/ckfinder/userfiles/files/98215427749.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/93037866960d46b0a40de3.pdfIn PDF document text
    • http://www.benyowsky.com/resources/files/9955188468.pdfIn PDF document text
    • http://aven.su/userfiles/file/momilepodi.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/256b7357ebcfa4e2b3f70d4de7e1a85e/koluxodefojudoso.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160725137f2d6c---59878844119.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a55f351d540---8883203923.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc7890b137---wabiwemikomutodugunubupe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=aromatic+organic+chemistry+pdf+notes+class+11PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA2 11212 bytes
SHA-256: 51141df31ff84d8718f9b4aa68998380860c15e81188b5d275fc456a6e87dbfc
font_01_sfnt_off0000f596.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF596 16944 bytes
SHA-256: b2f3c8e22965cd847ee476499278b499d310d17e34c97d3c0bd4547d0c506371
font_02_sfnt_off000121ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000139ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139FF 16312 bytes
SHA-256: 7d15b2d6d265aaca51dda18faee70a1b8fa9d95ed54cb111fb0895789092f9ae