Malicious PDF — malware analysis report

Static analysis result for SHA-256 a21b09389a59a9a4…

MALICIOUS

PDF

74.6 KB Created: 2021-07-13 10:49:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 3102e9ae4eb0ccbe362c5d6fc16e6697 SHA-1: 8ec549dd2f264dd6bd9d7cce6d7951deb0d3adee SHA-256: a21b09389a59a9a4b647e92b2c132471e448d40d2940f586960bc6ee290a688c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/o4t2r904en927l8nnbre6dafm0/xamotewelovameseniwodu.pdf In PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160891743d018f---kexumazafesejaxoj.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/20491930280.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607857f69b369---99511110541.pdfIn PDF document text
    • http://chalappuram.com/userfiles/file/50594293255.pdfIn PDF document text
    • https://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/81642248251.pdfIn PDF document text
    • https://avenue102.com/uploads/file/xasizobewepekaku.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/3642639068.pdfIn PDF document text
    • https://akarchlight.com/wp-content/plugins/super-forms/uploads/php/files/7a3f6463a0ad30857a047451b43e304b/mobowosekozuzepifu.pdfIn PDF document text
    • https://elbag.net/wp-content/plugins/super-forms/uploads/php/files/df86e380ab2e354eef55e0e6e463f433/wekeku.pdfIn PDF document text
    • http://martom24.pl/martom/userfiles/file/dugafinotokafafujixe.pdfIn PDF document text
    • http://blbr365.com/userfiles/file/1621333893.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/42246258890.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/2082ff289813be5366951f8a24f66022/64437570553.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073167b42cfb---45626240168.pdfIn PDF document text
    • https://viratrip.com/basefile/travelasreviracom/files/tivedapekaruxo.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160786bfdddce1---18489780151.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1608dd83e59a44---42666520255.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160707859b3505---zalavuvafevekidedun.pdfIn PDF document text
    • https://irantruck.ir/data/file/36767709854.pdfIn PDF document text
    • http://kpdb.org/userfiles/files/zosizusuvudigeti.pdfIn PDF document text
    • http://lowchens.org/userfiles/file/31393371122.pdfIn PDF document text
    • http://splogservice.ru/content/file/99270709884.pdfIn PDF document text
    • http://dspec-car.com/js/upload/files/mofamivoxak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=medians+and+altitudes+of+triangles+worksheetPDF 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_off0000c00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC00B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d822.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD822 10904 bytes
SHA-256: 85c07fb385aaf629949901afbacf08431ae11b0065bfd2bbfa765371de746ec5
font_02_sfnt_off0000f12b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF12B 16828 bytes
SHA-256: 194ff27180ce2c902f653d69dd69d480a5c6556feae2d3aaf7ad4870ec381cbd