Malicious PDF — malware analysis report

Static analysis result for SHA-256 e344b03a51eae21a…

MALICIOUS

PDF

90.0 KB Created: 2021-05-19 14:44:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 00d9701d20e0a5c4a0131e4161d76c4a SHA-1: 44fcdd7e7558b80d1eeba2e5175ab9879fb207e5 SHA-256: e344b03a51eae21a5db58fd2e6f14d29643b15bccba3ba8fa8b30ea178df277e
156 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a significant number of external links, with one heuristic specifically identifying a 'PDF_SEO_LINK_FARM'. The primary malicious URL identified is 'https://kuzutuzo.ru/strik?utm_term=resumen+del+libro+romeo+y+julieta+por+actos', which suggests a phishing or redirection attempt. While no scripts were explicitly extracted, the presence of numerous external links points towards a phishing or spamming campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://kuzutuzo.ru/strik?utm_term=resumen+del+libro+romeo+y+julieta+por+actos
    • https://rokosogamutoluf.weebly.com/uploads/1/3/0/8/130873735/1198132.pdf
    • https://vikilegopufuber.weebly.com/uploads/1/3/4/5/134588451/d82a5b.pdf
    • https://dizakevusarebiz.weebly.com/uploads/1/3/4/5/134581037/2072093.pdf
    • https://bebotarusi.weebly.com/uploads/1/3/1/4/131454771/ce854d4b.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/56d163a7-72b1-4091-b91c-fecfdc1295c6/wooldridge_introductory_econometrics_6th_edition.pdf
    • https://uploads.strikinglycdn.com/files/6642ad42-199e-4520-b1d2-2af21ee68811/how_do_you_draw_on_the_right_side_of_your_brain.pdf
    • https://uploads.strikinglycdn.com/files/598507e3-f59c-456a-a8ec-2dc2277dbdf3/cafe_zupas_menu.pdf
    • https://uploads.strikinglycdn.com/files/ba569033-2e56-4b7d-99e9-3507ba510ea8/60937624444.pdf
    • https://uploads.strikinglycdn.com/files/31eb9a93-7924-4f19-99af-9d6c329ba082/how_to_stretch_a_karate_belt_wikihow.pdf
    • https://uploads.strikinglycdn.com/files/b491de76-a90b-4774-84e3-97917091a85e/89352515211.pdf
    • https://uploads.strikinglycdn.com/files/7d6c3967-ac33-4b6a-93c7-ca2f60c5435c/passing_nella_larsen_quotes_with_page_numbers.pdf
    • https://s3.amazonaws.com/xiwevitox/2449029651.pdf
    • https://s3.amazonaws.com/tesotiwapax/davekepovaju.pdf
    • https://uploads.strikinglycdn.com/files/57fffdff-7f38-4e08-9359-b2622ade1efb/7710765226.pdf
    • https://s3.amazonaws.com/pusolefosex/spirit_of_praise_elshadai_adonai_song.pdf
    • https://uploads.strikinglycdn.com/files/b688cf52-7b97-4153-8118-64ff7ca4ef47/27514363849.pdf
    • https://s3.amazonaws.com/sugosubexez/lirr_train_schedule_huntington_to_penn.pdf
    • https://s3.amazonaws.com/rizijubovapuk/77147722154.pdf
    • https://uploads.strikinglycdn.com/files/cf067ec8-aa7c-4a65-8a9b-08eaf406f9c9/honda_rebel_500_for_sale_fresno_ca.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011ca7.bin
38a58a1469d30240a90e1f1903b6b892c3081da461ce0f7a29bed91029561912
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA7 5544 bytes
font_01_sfnt_off00012f72.bin
648807ad46d29c4c496e5e00bff46ebe87c5dcc97c8d40001636d321471fa102
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F72 13212 bytes