Malicious PDF — malware analysis report

Static analysis result for SHA-256 16b169bdd1ecf100…

MALICIOUS

PDF

95.4 KB Created: 2021-06-30 09:48:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c5cb87cd886f042a360f71a6736bc93c SHA-1: 8ba649b2a5319236267efe729bd09274968b48ed SHA-256: 16b169bdd1ecf100be69c07f908606be302b7b64a5513c490e07ada4de45fe16
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL analysis point to a malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e553ab162f---kakomemudexotapuvosag.pdf In PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/99823fbc3950d15e297b09e39370acb6/tegavasaz.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095c55f774b6---vemijomolejodoladimi.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078495b5d859---13965573749.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/babe1ce0353901d9102bc7365959b361/64582363436.pdfIn PDF document text
    • https://koratspring.com/upload/file/sikuzidipefedunufuvum.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/84563119534.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb808b728a7---wanawakerudalanemap.pdfIn PDF document text
    • http://creatinglifeoptions.com/userfiles/files/voxud.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/cdceda83b279c1923aa4e2c5f6628d56/15733361200.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098b043c7981---33657152429.pdfIn PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/nokepasaxan.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/n2r5j4i4c9rp9mkp5uu6j2vtu1/kifagavikug.pdfIn PDF document text
    • http://bjsprt.com/uploadfile/file///2021061922430479.pdfIn PDF document text
    • https://ntiverification.com/userfiles/file/tozegubuxob.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/rs0c8rlkfnnk24bbaackat6tk7/33031818106.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/64032652164.pdfIn PDF document text
    • https://akita-inu.lv/www/files/files/gemazugugijiki.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160864f899fa09---94339258087.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/90a5e86e3ba94f38f877a289095ad49d/xidipusumakenajelokijitu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=design+of+reinforced+concrete+9th+edition+solution+manual+pdfPDF 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_off00010f8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F8C 17508 bytes
SHA-256: b738cdf81f7df7268fcbe050c09c2f667ae33f8aaa3652374ba0a04b685a6a9c
font_01_sfnt_off00013db1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DB1 11336 bytes
SHA-256: 65526347bcc6ac3aac3d527b32f123011adf094759e95a88ca398f03b67c8a5f
font_02_sfnt_off00015806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15806 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1