Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa822c9d8bd4d4f7…

MALICIOUS

PDF

86.8 KB Created: 2021-04-29 00:06:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 17c6a0c30ee28520089c8ebaae13c9a8 SHA-1: d74d471ba71f1e8f66221e5550711275fbf53bb7 SHA-256: aa822c9d8bd4d4f7ee068e8e69593ca0246ee3e54dc6e4722d956ae47655cfc3
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable domains and are flagged as link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The document body, though heavily obfuscated, contains references to 'Biblia de estudio plenitud gratis' and the authoring application 'wkhtmltopdf', suggesting a lure to disguise the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • 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 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/strik?utm_term=biblia+de+estudio+plenitud+gratis PDF link annotation
    • https://cdn.sqhk.co/botonerepap/j1pNpUn/hair_salons_near_me_open_today_near_me.pdfIn PDF document text
    • https://cdn.sqhk.co/xawodoze/4miHn2N/real_steel_robots_for_sale.pdfIn PDF document text
    • http://jokojujut.medianewsonline.com/32348918807.pdfIn PDF document text
    • http://lawusuzad.iblogger.org/when_did_the_great_depression_start_and_end.pdfIn PDF document text
    • http://fukiwurezopukof.mywebcommunity.org/vepowageni.pdfIn PDF document text
    • https://cdn.sqhk.co/pumapajewa/iHjgj4h/tovulaxajimizaxezalab.pdfIn PDF document text
    • http://nokasosozigof.mypressonline.com/new_general_mathematics_textbook.pdfIn PDF document text
    • http://setafugeridol.scienceontheweb.net/genetic_predisposition_to_cancer.pdfIn PDF document text
    • http://wasegulom.mygamesonline.org/ca_dmv_written_test_answers.pdfIn PDF document text
    • https://cdn.sqhk.co/xisofofumew/4gfkFgi/pixel_studio_art_animation_mp4_gif.pdfIn PDF document text
    • https://cdn.sqhk.co/tinajugezepi/GjhWjcR/rocktron_banshee_2_manual.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zopimubusa.rf.gd/how_do_i_connect_my_bose_remote_to_my_samsung_tv.pdfIn PDF document text
    • http://mijizukegogetip.epizy.com/hoodsport_hatchery_fishing_report_2017.pdfIn PDF document text
    • http://katezoluvezile.epizy.com/22690769429.pdfIn PDF document text
    • http://lurolubudoruk.onlinewebshop.net/baby_girl_names_that_start_with_c_or_k.pdfIn PDF document text
    • http://xesidif.epizy.com/paradise_lost_poem_analysis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/efd4c223-f682-4a97-8c1c-e68e220b9aec/mr_heater_horizontal_vent_kit_instructions.pdfIn PDF document text
    • http://dinixikidimed.epizy.com/relevance_of_biological_clock.pdfIn PDF document text
    • http://sobawen.rf.gd/laxupokukidagonane.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eeea25c7-a74f-4eaf-8d1e-c8d1bcc77ffe/definicion_de_primeros_auxilios.pdfIn PDF document text
    • http://gusadixesexa.epizy.com/bumiz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b96ecba5-aaf9-4906-b22f-233e969b759e/zigigesatif.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f353.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF353 5316 bytes
SHA-256: af2bb5eaefa892d5a36e0da586ffcc718715aedbf70881b603cf6de506498c7a
font_01_sfnt_off00010566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10566 1828 bytes
SHA-256: 7221b4bace084398c07fcaddafb47ad6fb9a36da41183ba7284a79c3fd661164
font_02_sfnt_off00010e5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E5F 13300 bytes
SHA-256: 460f68802a7b1d4521af637418908838c1e4bff3d7b517021a67eff206d3e0af
font_03_sfnt_off0001382f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1382F 16060 bytes
SHA-256: df1d2c903cabdf2976887e260da0b25217edeb5ce2b71f315001024534e8e210