Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f3805bf745b23a2…

MALICIOUS

PDF

79.8 KB Created: 2021-05-06 14:40:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: c50828ac9bb33c68feda64dd334f4661 SHA-1: 5e7d9157e3e98f717dcbf3fa15a3a80498a86576 SHA-256: 0f3805bf745b23a26332f870526390e08f7d0fa45e31a0508f09897d1d113cb3
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of an external URI pointing to 'midufefew.ru' with a 'how to not answer personal questions' UTM term further supports a deceptive purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://midufefew.ru/strik?utm_term=how+to+not+answer+personal+questions PDF link annotation
    • http://nenegifivujaxu.mypressonline.com/41210331452.pdfIn PDF document text
    • http://sufulilutidake.mypressonline.com/1754438888.pdfIn PDF document text
    • http://lowufadit.scienceontheweb.net/bogy_s_babca_virgai.pdfIn PDF document text
    • http://dinewegivogofe.mygamesonline.org/24658001871.pdfIn PDF document text
    • http://tejasatobes.medianewsonline.com/13629991758.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://uploads.strikinglycdn.com/files/33df6bc5-f6eb-4839-982e-aaac2c138bf7/wowuwupetexazavovo.pdfIn PDF document text
    • https://0e01c86c-6ad9-43de-bc04-b8819f410213.filesusr.com/ugd/73c254_adcff340d99c474a873ba037fe13b7e9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a8c978b9-9509-444f-993f-e947f2193787/how_to_turn_on_dyson_ball_vacuum.pdfIn PDF document text
    • https://s3.amazonaws.com/satedafadusizo/tidolaxewaretonavaba.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a74160fa-c251-43c0-a112-62364e663053/88632291862.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/023a3b67-3d67-4646-8cba-7ae0e9fdae88/how_to_change_blades_on_mower_deck.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6c39e324-6ca2-47a2-b17d-adb3fc8a2dae/badger_insinkerator_installation.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/17cfe94d-957f-4b35-84d6-0a0d42a62beb/philips_respironics_remstar_auto_a-flex_manual.pdfIn PDF document text
    • https://21e323bd-7fdd-46e9-a6c7-4880e76d7610.filesusr.com/ugd/0a51c1_c3027c490ab9464897486037a097dcc6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/106e66e1-5216-458d-80fa-73b6d4e0c400/bubobasipotazan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a6236843-8c09-4751-9ca9-5a6212d8e184/how_long_does_thermometer_stay_under_tongue.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1694718-09df-4ef3-bf9a-5e2772058836/40545901818.pdfIn PDF document text
    • http://nukilaba.myartsonline.com/review_buku_the_magic_rhonda_byrne.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ec2a4968-f4f6-43e5-ae7b-ec42e0c0636e/12273017903.pdfIn PDF document text
    • https://s3.amazonaws.com/genedonapubefe/what_does_a_baby_rainbow_lorikeet_look_like.pdfIn PDF document text
    • http://nunavaxukozu.onlinewebshop.net/ethylene_glycol_msds.pdfIn PDF document text
    • https://fc060a1e-8c1d-4b7d-bafd-75f79d4c6355.filesusr.com/ugd/c0a468_ee8b85dee2264f1bbadf5c0e03f5eb9c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/rufonali/63732906568.pdfIn PDF document text
    • https://s3.amazonaws.com/libosokune/how_to_clean_electrolux_vacuum_hepa_filter.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_off0000ed30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED30 4876 bytes
SHA-256: eb63aaee395119ec736396826f245797d401870da9e542c3b4418e1006c61884
font_01_sfnt_off0000fddb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDB 11276 bytes
SHA-256: bb6d1631d5d2055a9c69dde9db9aa271766680a337238f86d5a7260f0498dd3c
font_02_sfnt_off0001235d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1235D 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333