Malicious PDF — malware analysis report

Static analysis result for SHA-256 6dfd42749b6c4138…

MALICIOUS

PDF

85.6 KB Created: 2021-05-25 00:51:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 858e90e028f88b13df7e14203eb1e7b8 SHA-1: 9cc023796c7bf55996bb9b808b22e875c26ee43f SHA-256: 6dfd42749b6c4138027ab1870f8a9d8959db05d8dcd24556510ae5f30593f66c
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://ponafet.ru/strik?utm_term=what+is+the+format+for+an+argumentative+essay PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4380237/normal_5fd0533b65800.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419192/normal_606ba956033ca.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454043/normal_6016c9e200506.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409103/normal_600e883ca9a68.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385613/normal_605f6267f35bc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416326/normal_60185fd9e0d46.pdfIn PDF document text
    • https://jumedewumeba.weebly.com/uploads/1/3/4/3/134310957/lejijapufa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449789/normal_6012fdfee250a.pdfIn PDF document text
    • https://napokepuwaju.weebly.com/uploads/1/3/1/1/131164128/depewukaw_xegimanapigeti_sagebebamobef_besezesijogazo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475203/normal_6002761139d26.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376625/normal_604d950fa0e98.pdfIn PDF document text
    • https://kalujobad.weebly.com/uploads/1/3/4/3/134390175/e694f3725b3.pdfIn PDF document text
    • https://divuvefa.weebly.com/uploads/1/3/4/7/134759037/e5860e4800634.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417809/normal_6063dbfc99c04.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/7971011c-5b81-4c47-ab31-d6c7b325ceca/97629796453.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a73898e-6c66-4e1d-90d3-97831c36587d/walmart_twitter_ps5_pre_order.pdfIn PDF document text
    • https://s3.amazonaws.com/sazomo/linux_commands_with_examples_in_hindi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0664ce1d-e08c-422a-9d0b-94ad848c1c3f/rezafekabewumuxapemeri.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd5c9757-c959-4b1a-8cc7-c0ada9b97d0d/benivo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9f7af79-4baa-4131-a86d-633c494e0691/14685006202.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5cc8feec-7820-4080-adf9-e40abab2b7a7/27328054155.pdfIn PDF document text
    • https://s3.amazonaws.com/begijufadi/making_good_progress_meaning.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/781ebe37-1b7d-48bc-832d-36f5f3246c33/what_order_are_the_artemis_fowl_books_in.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011120.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11120 5324 bytes
SHA-256: 024fb0756d94d1123c97258680f1b04bd944f3035951dff2ba5366137ddaab25
font_01_sfnt_off00012328.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12328 11424 bytes
SHA-256: 53110e1a81162362c0bbe2d74b750766f892e0d0fc56e61acacdeaca5d83a80e