Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a99c708cd905c5a…

MALICIOUS

PDF

143.7 KB Created: 2021-03-17 13:27:53 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 232b9d9d10169145b9d54b9d9afde8b2 SHA-1: 5be9e400c0dfabfdd2244f80b1ee8425bf76a396 SHA-256: 8a99c708cd905c5a5957addd99f7074e9afd55e376c5168106ae54b38e28a597
126 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF contains a large number of embedded links, many pointing to disposable hosting, suggesting a link farm or phishing lure. The presence of external URIs and the overall structure strongly suggest it's designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://vilenefex.ru/award?keyword=br+ambedkar+biography+pdf
    • http://sunazeremitiwu.mypressonline.com/veduluro.pdf
    • http://xedeporib.medianewsonline.com/88028594814.pdf
    • http://ribavid.medianewsonline.com/runir_plusieurs_en_1.pdf
    • http://fomijegi.mypressonline.com/what_was_beneathas_dream_in_a_raisin_in_the_sun.pdf
    • http://sokixatov.mywebcommunity.org/what_are_the_different_theories_and_models_of_organizational_behavior.pdf
    • http://dizititakozazi.mywebcommunity.org/spalding_basketball_system_u-turn_lift_manual.pdf
    • http://penafur.scienceontheweb.net/apowersoft_online_editor_review.pdf
    • http://pawusewi.sportsontheweb.net/anime_characters_birthdays_in_march_12.pdf
    • http://dosaxixapaxa.medianewsonline.com/degugoboroxupadu.pdf
    • http://nipokaxa.getenjoyment.net/boeing_737_800_specifications.pdf
    • http://wasatosu.sportsontheweb.net/vifosekuros.pdf
    • http://tujemet.scienceontheweb.net/74089946995.pdf
    • http://xumupizaxuto.scienceontheweb.net/xagag.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://fedorahosted.org/lohit
    • https://1b65b899-5fad-42bd-af9e-a3fb1d6a4c80.filesusr.com/ugd/a2ebd8_f0038231adae405889f316c91c4f5511.pdf?index=true
    • http://vugugemo.atwebpages.com/buzubosaxozu.pdf
    • http://kosatalek.rf.gd/xenosulurujamapo.pdf
    • http://luvabokinoleg.onlinewebshop.net/dedunumafebiz.pdf
    • https://0c7b1e5d-10e9-4c66-9a64-57e6babc74f3.filesusr.com/ugd/6b59ba_70dccaff7675478d9c9e0fc7f48dc67c.pdf?index=true
    • http://gozulejawefufap.epizy.com/80356861578.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001d3ea.bin
dae836cc3cf0126792c054f99a474898f3b3d6ee03926333cff3f655b5ea5295
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D3EA 5600 bytes
font_01_sfnt_off0001e6d9.bin
e5c8b693166a3eceb4edaa38fcbb7188ef867222a162e3a70a2442587c46b382
pdf-font-stream PDF embedded font (sfnt) at offset 0x1E6D9 13420 bytes
font_02_sfnt_off000212f1.bin
94ff3f50e7fc041840224c2e5ec0c9165fca7037b845b4798e627605c46cd131
pdf-font-stream PDF embedded font (sfnt) at offset 0x212F1 9424 bytes