Malicious PDF — malware analysis report

Static analysis result for SHA-256 b51fa61ea4f4d011…

MALICIOUS

PDF

84.2 KB Created: 2021-03-12 04:06:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: e84559d4630ee7ef90fb64adeb90feef SHA-1: aed54de2427b9b77096a9fce0c1ea990d060c0cb SHA-256: b51fa61ea4f4d01173e38dbc5072d4d5a6d541471f78ba6be86986dcf3c6f37f
126 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or redirection scheme. The ML classifier also flagged this PDF as malicious with high confidence. The presence of embedded URLs and the nature of the link farm suggest an attempt to direct users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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://maypoin.ru/123?utm_term=leadpages+free+templates PDF link annotation
    • http://gepexoliv.medianewsonline.com/jotifexokageda.pdfIn PDF document text
    • http://winoorama.space/download_real_wrestling_3d_for_androidofbyx.pdfIn PDF document text
    • http://smotrikino.fun/803862185345xtbc.pdfIn PDF document text
    • https://zalivibutadugaf.weebly.com/uploads/1/3/5/3/135391941/jowokexis_pivukugepupijul_kamokusawitudim_xadibabexa.pdfIn PDF document text
    • http://decideyouself.fun/mugixasefifabojuputuizb2q.pdfIn PDF document text
    • http://mitatizizuje.mypressonline.com/78595009563.pdfIn PDF document text
    • http://vizazovabula.mywebcommunity.org/abundance_now_book.pdfIn PDF document text
    • http://bilet-pdd.site/antipsychotic_drugs_listnirwm.pdfIn PDF document text
    • https://ganakinupep.weebly.com/uploads/1/3/4/5/134599301/1321354.pdfIn PDF document text
    • https://baputopozim.weebly.com/uploads/1/3/5/3/135336161/1128517.pdfIn PDF document text
    • http://ziwigosopijulal.mygamesonline.org/71959721734.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://c5c27394-2042-4749-9b39-d1c24dcbd9f0.filesusr.com/ugd/e9b987_0c6554aa06fa45f1897c28710cf2e42a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/967f0cb3-0d32-4bde-8227-c0c75299396c/cuantos_kg_tiene_un_metro_cubico.pdfIn PDF document text
    • https://081e7fb2-604d-424b-9b75-a58d54a71a44.filesusr.com/ugd/abd6ea_25b7107bc53a4227b1b8afb9751f9f5a.pdf?index=trueIn PDF document text
    • https://7e70056c-c2aa-4e53-98c5-50750123c107.filesusr.com/ugd/f8ae5d_e39b03d76d0d45c3b8d6552d6cf91b8d.pdf?index=trueIn PDF document text
    • https://3f46bf15-0a8c-4e80-b3e5-a2e3bf90e008.filesusr.com/ugd/8e6e76_44fe460a4f6a4a2489b2fd92323ac862.pdf?index=trueIn PDF document text
    • https://746420f6-3007-491b-ba72-fd43be5094e5.filesusr.com/ugd/277b62_570d7e3074db4272b78bd3019ffe5ef0.pdf?index=trueIn PDF document text
    • http://xasagode.myartsonline.com/10600692196.pdfIn PDF document text
    • https://58eafb2e-ea74-4523-a1b2-d2e0fe9bfe54.filesusr.com/ugd/466fa0_39aac4171d1e418994013933d7e56049.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/edd8f977-4025-4873-814a-5145146f5ebf/seasonal_unemployment_definition_examples.pdfIn PDF document text
    • https://c2267750-1f6d-4c2f-944a-eb302c7f07d7.filesusr.com/ugd/93971e_30f1c8fbc0134a4d9425dccd3cf31814.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c8899117-e4bb-41fe-af09-51d478ec8432/41740180233.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_off00010d98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D98 5300 bytes
SHA-256: 174303890a97740f098aedd2d5b5e8f08e5e03cf02099b83c953259585836c24
font_01_sfnt_off00011f95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F95 10636 bytes
SHA-256: 7748be8b3b8409aa41dae2cb57771522cccbe5cc64487e88595431ef103b2e3b