Malicious PDF — malware analysis report

Static analysis result for SHA-256 af8eaa7b098361e0…

MALICIOUS

PDF

84.6 KB Created: 2021-09-08 00:09:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 55bb39ad36adcd5b2b628ae5defdbe0c SHA-1: 7ff9aae8a7033126705b1eff26b7fca8fed207ca SHA-256: af8eaa7b098361e0953692e3a08b899b1c524b089f95183b4af5552015f36037
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and a link farm pointing to multiple compromised websites, suggesting an attempt to redirect users to malicious content. The presence of these elements strongly indicates a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://ventiliatoriai.lt/js/ckfinder/userfiles/files/93806514947.pdf In PDF document text
    • http://ccswcd.com/userfiles/file/lawide.pdfIn PDF document text
    • http://theurbanbazzaar.com/userfiles/file/11798049588.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/5809251114f9bd43a1ad281e3e235ffd/93099147594.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/c8fe459f4d5fa137cb1dada19131d147/99796165775.pdfIn PDF document text
    • http://mid-europe-ex.com/53538033954.pdfIn PDF document text
    • http://meskerjager.nl/media/files/77244248377.pdfIn PDF document text
    • http://24horasnoar.com.br/ckfinder/userfiles/files/64639503312.pdfIn PDF document text
    • http://tangiahoang.com/skinkorea/Images_upload/files/pawumodesuzumadumisare.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/c1c39cb25d0641e7137cbc37940bb7d6/81838981664.pdfIn PDF document text
    • http://promocode.lu/userfiles/files/rekijovilel.pdfIn PDF document text
    • http://frezerovka.by/images/fxeditor/file/bijapupaxewineniruv.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/bfb14acc1b40b1a7e5a7c703f03c479e/pipelenivat.pdfIn PDF document text
    • http://camonetinternational.com/files/file/karefatatifagekuwumudaka.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/16075b26a5f190---rupugosimejogemi.pdfIn PDF document text
    • https://themalc.org/files/file/87124721523.pdfIn PDF document text
    • http://bvsaigonbinhduong.vn/uploads/files/xalikukakaxoreloraxixo.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16091b6509ab71---12066613543.pdfIn PDF document text
    • http://smolensk-bakaleya.ru/userfiles/file/bamowasasoka.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/20216231415585500.pdfIn PDF document text
    • http://statewideroadservices.com/clients/879378/File/tipul.pdfIn PDF document text
    • https://secolink.sk/userfiles/file/45540303043.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cdbb2edcaa---tisuboxavadilag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=commutative+property+of+multiplication+worksheets+grade+4PDF 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_off0000ddc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC8 11632 bytes
SHA-256: d7ed9d42708a9c182ded8d86ddbb8bb17a9ca0803c76fb44ad956ba25aaa66fa
font_01_sfnt_off0000f936.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF936 19532 bytes
SHA-256: 41029bbe633b7d69b3779b30674534e1247f3ad27d55f54a700c2c6b74d9292e
font_02_sfnt_off00012bc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BC6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1