Malicious PDF — malware analysis report

Static analysis result for SHA-256 35dfa5b9d23d3a91…

MALICIOUS

PDF

93.1 KB Created: 2021-07-06 00:38:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 83c232f8c43dfadf6a31fd96f6cb3006 SHA-1: e6aaeb5a5a5410865b375a28b62b99a857f9c97c SHA-256: 35dfa5b9d23d3a913fc55a166abf013e478ed3e15f68affa3667868c9ba9ff8e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of threat. It contains numerous links to compromised websites, including WordPress installations, suggesting it's used as a link farm to redirect users to malicious content. The presence of external URIs and link farms points towards an attempt to distribute malware or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://inwebjor.ru/uplcv?utm_term=litany+to+the+blessed+virgin
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/df68828fd1723cf570a08553a57a84b2/dowiximozanud.pdf
    • http://sotel-perm.ru/site/file/48728638156.pdf
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/ab89fba6c38d72ad79fbdc48941b8516/bukega.pdf
    • http://hhsbluebirds1967.com/clients/b/b5/b592d679e9980e62d9d56be1bfb8b6b6/File/46631961852.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/gjm1qie3m7l1depshsidcjjgi0/xavitijixopi.pdf
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607a237d29ec1---fijiparovulotigawo.pdf
    • http://yepuco.com/uploads/files/vevavumigobegu.pdf
    • http://langfordfinancialservices.com/userfiles/files/84202026163.pdf
    • http://splogservice.ru/content/file/12494292318.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cdd67506d5---10568182976.pdf
    • http://chieucoingason.vn/files/gejogaji.pdf
    • http://pogservice.ru/userfiles/file/lavigirumobogeze.pdf
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16080c8fe7526a---tipisonitupatenabato.pdf
    • http://musorcentrum.hu/files/article/file/lodigebomazukibiru.pdf
    • http://ahcxdq.com/uploads/file/022337532581.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607383f31c596---66289882131.pdf
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/7913abd1a34ff376c21b73a6fd9aae72/79695898959.pdf
    • http://chokmanee.com/userfiles/file/33964690124.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160d6ce442b336---ditebuziwurotumenuziboraj.pdf
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/97da13731327436662420a491dbece02/43605776111.pdf
    • http://zubrcup.by/files/files/posolevexutugukal.pdf
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8cd03e4981---16957388162.pdf
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9fd9a54db1---79406902579.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105ff.bin
6f456682dbe4ba11fa0cb0ac6b46f0775dde1b61f5fabed3df20b37c03310105
pdf-font-stream PDF embedded font (sfnt) at offset 0x105FF 18940 bytes
font_01_sfnt_off00013682.bin
1e6955f9623c18f6366ba811546d948f9a651f5662302dbd03f58435ace5aaae
pdf-font-stream PDF embedded font (sfnt) at offset 0x13682 10804 bytes
font_02_sfnt_off00014f24.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14F24 16792 bytes