Malicious PDF — malware analysis report

Static analysis result for SHA-256 51a34b83f1a898d2…

MALICIOUS

PDF

78.3 KB Created: 2021-09-18 06:18:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1d901c311634df9854e060f90ed031e9 SHA-1: e3cdb537dec7caa114f0287136e1806fc7681e3e SHA-256: 51a34b83f1a898d2ec7876e6038ddd5eae99c353a50ae358ed6bda07429fdd27
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, flagging it as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable hosting. The primary purpose appears to be redirecting users to malicious sites, likely for phishing or further malware 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 http://uro-medical.pl/zdjecia/fotki/file/miwibotoleposa.pdf In PDF document text
    • https://clifestyle.net/uploades/userfiles/file/fewobawususefivuvokilax.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/c210946a4c08421ce25862c3e315c8c9/45326845416.pdfIn PDF document text
    • http://qianxi.cn/filespath/files/20210906195432.pdfIn PDF document text
    • http://seyrimerdin.com/userfiles/file/famozuvanuzew.pdfIn PDF document text
    • http://cuathepvangohaiduong.com/images/ckeditor/files/xowigutit.pdfIn PDF document text
    • https://fabriziochessa.it/userfiles/file/likurozokepi.pdfIn PDF document text
    • https://www.renfrewareahealthvillage.ca/ckfinder/userfiles/files/rilako.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/10526465481.pdfIn PDF document text
    • http://shanghaicruiseparty.com/uploads/file/diniba.pdfIn PDF document text
    • http://ecoaga.com/documentos/file/61376645722.pdfIn PDF document text
    • http://benly-carson.com/product/files/zivesenowukidizudusame.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/68758391991.pdfIn PDF document text
    • https://cosplay-expo.it/ckfinder/userfiles/files/xigezipuxijuzuko.pdfIn PDF document text
    • http://nanouklid.cz/upload/file/34362777513.pdfIn PDF document text
    • https://mimpishio2.com/contents/files/97581465205.pdfIn PDF document text
    • http://naviway.su/upload/files/gosojuvipoxobawiguvama.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/b2c4c46c903da01249eb7772a91a9b71/99481202009.pdfIn PDF document text
    • http://www.grupoaccs.net/ckfinder/userfiles/files/45995286588.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/83884441278.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/4r958l0e2itqeunhakprb4ipr4/nulaxudupir.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/sofuvemewejadajumuvu.pdfIn PDF document text
    • http://crystal-lamp.ru/uploads/files/wugujixemofasuwaruso.pdfIn PDF document text
    • http://irvinenott.co.uk/ckfinder/userfiles/files/15161525709.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=3d+illusion+wallpapers+for+androidPDF 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_off0000c2f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2F8 10656 bytes
SHA-256: 7171c693b43df825b023e8ae748f5cabd6acace283cffffa3a90df40a4a71cfe
font_01_sfnt_off0000db84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB84 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f396.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF396 22164 bytes
SHA-256: 38b2ef41b2e23b8096957e0fc01a633c425cdca7a91a395cb18460e92b4ff5db