Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5227e4592375d91…

MALICIOUS

PDF

98.5 KB Created: 2021-07-13 13:09:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 6c78d76ff16eb5c08f10fd36186c16d1 SHA-1: 8cfb58b99dd80fc426a607029347e7136466577d SHA-256: c5227e4592375d913d873d7aa90e5138b15b09f3bcad0c68e465771d6fb96216
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous other PDF files hosted on potentially compromised or disposable domains. While no scripts were directly extracted, the nature of link farms in PDFs often involves JavaScript to facilitate redirection or exploit vulnerabilities, suggesting an attack pattern aimed at phishing or distributing further malware. The presence of multiple links to PDF files on various domains points towards a broad distribution or evasion strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://rainbowcaterers.in/userfiles/file/59359574711.pdf In PDF document text
    • http://tunglamgarden.com/images/fck/file/83999772621.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/11926377632.pdfIn PDF document text
    • https://umartravel.com/files/mebogaziliduzog.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd16d47dca---zeguvarifeviwonamixev.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/vizosabugibofot.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a251fd217e8---sajoponagudodudawulugorej.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/afcf8b41369599180ab1dda3c3468072/31114141325.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/81716517943.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/livefatafosa.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/cfa0df8814be201df799e8f6ee8369a2/98526243831.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/bodoxunavupofibululaladix.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944ed4a316c---92773847015.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/1p14vb3sbj4kf8rp2eiij0r0ur/27471064139.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1c6120c40---dexodozogozor.pdfIn PDF document text
    • http://ridendo.cz/files/file/95190078748.pdfIn PDF document text
    • https://secolink.sk/userfiles/file/7656117544.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfdb35a4fd9---tekojoribexabug.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c0c9a16fa---namoragatulu.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d015badfc06---tonugam.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/29746314220.pdfIn PDF document text
    • http://dagmare.de/userfiles/file/8063179498.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/6839201778.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/74340462074.pdfIn PDF document text
    • https://smilepaper.tw/archive/upload/files/75897796952.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=cbse+sample+paper+2020+class+10+science+with+solutionPDF 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_off00011dec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DEC 11292 bytes
SHA-256: 2639150c700ba8d30f1ed0d267ab8ba77440bc79087f97dd66d26cab58a60552
font_01_sfnt_off0001382d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1382D 16884 bytes
SHA-256: cc2a3f3479d3bee70661eb60f78e5b2c0133aec4a7ecc4f2e1b8e5ccae90ed04
font_02_sfnt_off00016447.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16447 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1