Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8bdde8c8f3deec5…

MALICIOUS

PDF

74.6 KB Created: 2021-06-10 03:43:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 1ee6523c786421f8b5756ef3c0235805 SHA-1: ce247625dcef0264930d0091378a5bdb4f1570f3 SHA-256: a8bdde8c8f3deec518ba990dc4fba9afc69ab4bb0ad9424d44f5c6abcddde048
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 0.9997

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://nomylo.ru/pbw?utm_term=sonic+the+movie+coloring+pages PDF link annotation
    • https://wupugosow.weebly.com/uploads/1/3/1/3/131382590/da151521d48c7e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454547/normal_601061de3b716.pdfIn PDF document text
    • https://puwakama.weebly.com/uploads/1/3/4/4/134474688/e7eca87e6806086.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380869/normal_604e784463899.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425908/normal_5fc8f95f8fe40.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387035/normal_5fd8b70d34267.pdfIn PDF document text
    • https://jevizaja.weebly.com/uploads/1/3/4/8/134869407/tosenoromekatomor.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/85433a55-b6c4-41e6-8277-23ddff583da2/menuwebek.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/02f7836d-cabd-4ed2-a7d6-a8fabe991052/vodegusexel.pdfIn PDF document text
    • http://nugewil.pbworks.com/w/file/fetch/144649347/18233266236.pdfIn PDF document text
    • http://xulajirose.pbworks.com/w/file/fetch/144624051/33285608842.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55ad9790-97cb-46f0-a188-7da944baab15/the_tcp_ip_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/45286bdf-fe77-4311-8af8-ec4bbd120310/what_is_scalability_in_health_information_systems.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/94c73dc8-4bcf-498b-866a-b2f09b5b4548/tivodiweponofisalilexumob.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/edbeefa0-18dc-4799-99a0-2abc0856eb45/how_to_find_hydrogen_atoms_in_a_formula.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e99fa7fd-14df-42e8-a08c-05563d2f8ac8/potot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2d60cd7c-a1f1-4749-baf4-b51b3b30a5e8/how_to_add_hotspot_to_straight_talk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9acadc57-b937-4f92-9579-ef43861f1feb/formal_charge_practice_worksheet_with_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d9deca8-243e-4cac-a3b1-c3ebcada841e/89051550061.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b9a806d2-eda1-44b4-84cb-2e961c2004dd/74650472484.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a1b32e3-76a5-4c46-955b-0d3cc3720f31/stardew_valley_cheat_item_mod.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_off0000e80e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE80E 5512 bytes
SHA-256: 6fe83d58a44fc0c0c259bb17ddf288c012dc40f6bfb194d24eae66c87821c5ff
font_01_sfnt_off0000faa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA5 10260 bytes
SHA-256: 7b96632f21c73d1c31f08c05aad125d797e8293ac2cdcd13d078f12c14eb729a