Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac9b95717e33b0bd…

MALICIOUS

PDF

89.3 KB Created: 2021-04-01 05:08:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 7829428697b1c73688a7770d4094283e SHA-1: f13308fa191b484b5f556894f1ff0a31594c0513 SHA-256: ac9b95717e33b0bd9402bc37eeacebfa16b3bc505110037f42a91f206863481d
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The primary URL, zajinet.ru, is associated with a search term related to software installation, indicating a lure. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://zajinet.ru/strik?utm_term=how+to+install+c+compiler+in+windows+10+64+bit PDF link annotation
    • https://rusokupos.weebly.com/uploads/1/3/4/4/134468665/sagik.pdfIn PDF document text
    • https://godanikepogi.weebly.com/uploads/1/3/4/5/134509841/a37d5c83ec46e8.pdfIn PDF document text
    • https://lilikegemuvil.weebly.com/uploads/1/3/1/3/131398424/9ff80314fda93c.pdfIn PDF document text
    • http://xubozogafajus.22web.org/ark_mobile_engrams_guide.pdfIn PDF document text
    • https://dalegoronatodul.weebly.com/uploads/1/3/4/3/134309481/josaxepubenabugunubu.pdfIn PDF document text
    • http://nofubajabuv.medianewsonline.com/83317923650.pdfIn PDF document text
    • https://somirurawepaf.weebly.com/uploads/1/3/1/3/131381963/8676255.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/353894a9-9631-4dfb-8232-3cd72e0e5b3f/how_to_install_britax_pioneer_harness-2-booster.pdfIn PDF document text
    • http://xarozitapakegur.epizy.com/chikki_mukki_tamil_movie_songs.pdfIn PDF document text
    • https://63c5840e-267c-49ed-94d3-fc9f9d8b9c0b.filesusr.com/ugd/8c5bc8_409e30c2024b41b5afed613a1411e04e.pdf?index=trueIn PDF document text
    • http://tonavisuma.onlinewebshop.net/41455629860.pdfIn PDF document text
    • https://ed21222e-fee3-4fab-8b52-e2ddb7bb35ab.filesusr.com/ugd/e73fea_e658ac697b0f4aef88cd98338b8a689b.pdf?index=trueIn PDF document text
    • https://d2d87fd5-5f4d-49aa-ab3c-2263ce4b5d22.filesusr.com/ugd/9169d2_bd9bdd78fb694677afb6fd5f679633f4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6015441a-69d7-4909-9b53-ab305bc77a0f/78533615105.pdfIn PDF document text
    • http://lidiremuvuzanas.rf.gd/what_is_the_main_point_of_i_have_a_dream_speech.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6396a2b3-c295-40e9-b0e7-d98f522ef09f/what_are_the_four_disciplines_of_anthropology.pdfIn PDF document text
    • https://ee897e78-a157-4eb5-8a47-d615096087a2.filesusr.com/ugd/113e89_0f429c3c40b34409b69249fd0f6b0082.pdf?index=trueIn PDF document text
    • http://solugivewatewa.myartsonline.com/19672688140.pdfIn PDF document text
    • http://kemesid.onlinewebshop.net/1872938731.pdfIn PDF document text
    • http://lodusebivepakef.epizy.com/villager_trading_guide_minecraft.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
    • 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_off00010390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10390 5848 bytes
SHA-256: e9ebd17d76eb64ccabfa46c7037df43f3fe2e2a204802578becd32e8a5c900c3
font_01_sfnt_off0001176f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1176F 10468 bytes
SHA-256: 806d37961278279d3fc2c28875b4c8da213f87aee958fe5c5d517b79488a3d70
font_02_sfnt_off00013b8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B8F 18396 bytes
SHA-256: 439c5e985c6381d85555adf535bf80a268c07612db893f66d450da20272785cd