Malicious PDF — malware analysis report

Static analysis result for SHA-256 523ed12eafcf46c3…

MALICIOUS

PDF

76.1 KB Created: 2021-03-19 15:57:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: bd82c69cce4bc3b4b9f27d4cd24eb50a SHA-1: 0df8343a467012a3080ec98763f17a9de9cd4151 SHA-256: 523ed12eafcf46c3be83f96e3462c27dd37f704e2fd3a8bbe06afa2111141cae
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of external links, identified as a link farm. This suggests the document's primary purpose is to direct users to other resources, potentially for SEO manipulation or to host malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely involving phishing or trojan delivery through the linked content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nipisod.ru/award?keyword=imperative+mood+worksheet+pdf PDF link annotation
    • http://getcreditreport.info/tamil_numerology_books_in_english798js.pdfIn PDF document text
    • https://cdn.sqhk.co/fakodozug/lBhcjc7/xojarijuwakozakasulexutob.pdfIn PDF document text
    • https://cdn.sqhk.co/bufudoraxala/haibW1Q/10284876604.pdfIn PDF document text
    • https://vaguvijag.weebly.com/uploads/1/3/4/6/134610999/lubabiniwepaxolifal.pdfIn PDF document text
    • https://cdn.sqhk.co/sututidogo/IidkyC9/kixidavar.pdfIn PDF document text
    • https://deluwibenarut.weebly.com/uploads/1/3/1/3/131382693/1506551.pdfIn PDF document text
    • https://cdn.sqhk.co/joxusozomilo/gg2uYDI/854749595.pdfIn PDF document text
    • https://vorusasu.weebly.com/uploads/1/3/2/7/132740845/6498188.pdfIn PDF document text
    • http://scandisvet.ru/download_bblia_sagrada_powerpoint4kevb.pdfIn PDF document text
    • https://luzatewuxajexi.weebly.com/uploads/1/3/4/2/134265782/muloloki.pdfIn PDF document text
    • https://muvomajivogi.weebly.com/uploads/1/3/4/3/134373377/mixoxo.pdfIn PDF document text
    • https://cdn.sqhk.co/pesarukogi/O83chbh/hamlet_act_1_study_questions_and_answers.pdfIn PDF document text
    • https://cdn.sqhk.co/bijukipuj/hdhfshg/klondike_solitaire_free_no_ads.pdfIn PDF document text
    • http://investmag.org/how_to_get_a_220v_outlet3q66s.pdfIn PDF document text
    • http://icily.xyz/bon_jovi_greatest_hits_album_free7s74v.pdfIn PDF document text
    • https://cdn.sqhk.co/gevagedubop/jageiiy/magic_aquarium_fish_world_mod_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/risevejuxik/gBhe0gc/musicals_on_disney_plus_australia.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8c1dc56a-a131-4b43-acff-3635b9115217.filesusr.com/ugd/90423f_6bd0b403f77f493aa94a0786083b5bd7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ba32fbfd-dc72-4c51-82e0-7284ec3a9a45/ap_exam_calendar_2016.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4304bdfd-2243-4f5f-bd9e-a5eecd3c7c71/is_model_s_better_than_model_3.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a598f15d-4846-4d13-91f4-a177e78e1190/how_do_you_remove_samsung_ice_maker.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3a31862-6773-4822-b182-e1cdce9d0a29/how_to_work_out_arbitrary_units.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/15406417-f2be-4a7a-82f8-54e15a7d6d84/pinagenaw.pdfIn PDF document text
    • https://a82c121c-2200-4cd7-aff6-47cf910fdadb.filesusr.com/ugd/117c17_e2fe1ed9c6a5488587e1b6c465349ac1.pdf?index=trueIn 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_off0000eb66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB66 5400 bytes
SHA-256: 7438b3e62860174a360b185310112949d84697de260d5d878e714f6b9e467165
font_01_sfnt_off0000fdb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB1 10976 bytes
SHA-256: 898a18522a5a83ad00358755ead9ad09052ca469c52b03cab94821f14ff6dd58