Malicious PDF — malware analysis report

Static analysis result for SHA-256 755bc0a8955ad146…

MALICIOUS

PDF

93.6 KB Created: 2021-05-29 09:03:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 4b98bfea7f27ed59422664fffc825b4f SHA-1: e09a544cda774edf5183e0f0308f0f027812b18a SHA-256: 755bc0a8955ad146101a751d9edd4303606b1ec5b34d06504c31b4fe4c79bd57
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 of which point to disposable hosting, indicating a link farm or phishing operation. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body, though obfuscated, contains text related to 'gravimetric analysis calculations worksheet', which is likely a lure to direct users to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://bologen.ru/123?utm_term=gravimetric+analysis+calculations+worksheet PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4385876/normal_604f3a04b1e92.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384836/normal_603063c2998e6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454672/normal_5fcaa1a073b41.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375351/normal_6066185fdbd89.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390055/normal_60222389007d7.pdfIn PDF document text
    • https://votokivefanatu.weebly.com/uploads/1/3/1/4/131453133/lezozoxe_bomajutexi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424040/normal_5ffbaf9f75b2e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420434/normal_603ad6788e3d7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389358/normal_606da24931bff.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490122/normal_60468db1ef321.pdfIn PDF document text
    • https://sozivutapadonen.weebly.com/uploads/1/3/1/1/131164462/b3df8c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481999/normal_5fe6299d8c8ed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408195/normal_60224dfd70460.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490917/normal_5ff8586f983f8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384307/normal_6005ba5d83b57.pdfIn PDF document text
    • https://suwanozafedo.weebly.com/uploads/1/3/4/5/134587456/2941632.pdfIn PDF document text
    • https://jadanimotubow.weebly.com/uploads/1/3/1/8/131856100/mexixirudaw.pdfIn PDF document text
    • https://gixapogaruxa.weebly.com/uploads/1/3/4/3/134331356/4165971.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/b3971348-b27f-4262-91ed-e22d255b2659/habits_of_the_heart_lyrics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d0620dbd-f67a-44f5-a78d-59d396e2639e/my_cloud_desktop_app_windows_10_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e186e437-7200-498a-a6cf-5b35655b68a0/oleanna_play_meaning.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/25d7dfcb-e551-4340-90a8-9cf990ad99d1/what_channel_is_the_fire_log_on_directv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b89b9baa-2a2c-46e3-aa1d-129f69b75cb4/sopaxozerazatutawit.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_off00012d07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D07 5388 bytes
SHA-256: c27ce3ccaa36f7de1709bc9e5e47f1201b3a9149df42440f2c1331623078356c
font_01_sfnt_off00013f4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F4B 11616 bytes
SHA-256: bdedd876d94995df890c11eeac7ec74e2ad566783e907a80b80b09dbdfe0c080