Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c570dde4bef78d2…

MALICIOUS

PDF

72.0 KB Created: 2021-04-06 16:55:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 00137a5aba13bcf8c8c0e93541e27b7e SHA-1: 20abd901cb4f69e914ee2547069a71145b7af145 SHA-256: 8c570dde4bef78d26a74c236bd1eb00ebd84135560c71362d9e74b7cfc669ef8
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 0.9994

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://leonvi.ru/aws?utm_term=what+is+enthalpy+change+in+thermodynamics PDF link annotation
    • https://gimebupezepufo.weebly.com/uploads/1/3/4/5/134507041/8406055.pdfIn PDF document text
    • http://getinugalukef.iblogger.org/how_do_i_connect_my_atem_software_control.pdfIn PDF document text
    • http://wibevuzu.iblogger.org/telov.pdfIn PDF document text
    • http://kefinefure.iblogger.org/bio_rad_cfx_manager_software.pdfIn PDF document text
    • https://wozuxepu.weebly.com/uploads/1/3/4/4/134478893/bozowopan-dewasaxeketonob-serif.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://a54de82d-0003-4787-801b-d7ee719c780a.filesusr.com/ugd/8d57bd_f73db0bbabdf468bb8a48f77bfcc47b5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2bb5f933-d1e4-44a7-a445-9970c5936145/nusawiduwovalusoberu.pdfIn PDF document text
    • http://wipupagajefi.rf.gd/87564616964.pdfIn PDF document text
    • https://3f9320ff-391d-49df-b192-c557e211a93c.filesusr.com/ugd/469aea_4b16c670e7b542e394f8654e42511e67.pdf?index=trueIn PDF document text
    • http://dipimov.epizy.com/malekith_guide_mortal_empires.pdfIn PDF document text
    • https://d5aacb37-8766-4234-9cc8-c2ec3b911aba.filesusr.com/ugd/1e723b_9307d9fc0c304abab8dd42386bfbd236.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a8db0a78-aaab-4edc-b29e-6367e10714c6/strangers_on_a_train_alfred_hitchcock_full_movie.pdfIn PDF document text
    • https://8d90b851-447f-4cfc-ac95-1e867b71b983.filesusr.com/ugd/b371d9_8bc0161408ce4616b1c00361be7d5199.pdf?index=trueIn PDF document text
    • http://bipurufepibega.epizy.com/sasivaz.pdfIn PDF document text
    • https://e0f910ba-f4aa-4d6b-87f6-24d78cda99ab.filesusr.com/ugd/cc15ef_968c8af5c1d849bcbbfa6b855149dcce.pdf?index=trueIn PDF document text
    • http://rugafejowa.rf.gd/bosch_silence_plus_44_dba_display_not_working.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cdf175f9-df70-4a52-ad07-bdf3776eabb4/what_is_a_biological_predisposition_mean.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/622280bb-709c-49bb-99dd-9ea64f958185/16773278147.pdfIn PDF document text
    • http://jepatejefa.epizy.com/sun_tzu_el_arte_de_la_guerra_resumen.pdfIn PDF document text
    • http://lijizuzinarit.epizy.com/rixemamifaduvalujaf.pdfIn PDF document text
    • https://3f735f5a-cd1c-4288-bd93-adeff6e084d9.filesusr.com/ugd/bcc0e4_d6c29ff412af4968a40247d7ec526b62.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb8fcf30-b085-4ec7-a2f7-60a9fc30bded/how_to_learn_algebra_easy.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF4A 5388 bytes
SHA-256: e230ee02bffeaba7370a376244b50f3218773401cfe0417f34ced39df149641b
font_01_sfnt_off0000e171.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE171 9964 bytes
SHA-256: 1c9ed7a994a1b4951a5120ade58d3bcd8ace422a0f40e832bb87dce2e59a12cd
font_02_sfnt_off000103bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103BB 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176