Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c5e9d98abba7044…

MALICIOUS

PDF

86.0 KB Created: 2021-05-02 16:52:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 599efcb2afcebbcd2795e070f2b14931 SHA-1: 2513ce140d2284746c566701ce1c867f98d3879b SHA-256: 6c5e9d98abba70445bcb0f290faf1bc3451e3165a4c6d68aae19d4d94a98afee
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to disposable hosting or redirectors, indicating a link farm designed to distribute malicious content or phish users. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically identifies this behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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 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://gimoguvi.ru/strik?utm_term=vintage+precision+deluxe+sewing+machine
    • http://buwovavozu.getenjoyment.net/2622887268.pdf
    • http://ch-redirect.icu/tovixatetel3nx.pdf
    • http://copyrightshelpcenter.com/867580364003bu7a.pdf
    • http://jobediniberine.scienceontheweb.net/kemukododelupavol.pdf
    • http://nout-sale.site/sewuwaguga5y4rc.pdf
    • http://wojisub.mypressonline.com/subunadifekerew.pdf
    • http://xijulefabogi.getenjoyment.net/60285572584.pdf
    • http://zomaragexavope.sportsontheweb.net/free_printable_bingo_cards_with_numbers_1_75.pdf
    • http://ramuwesitavoz.mywebcommunity.org/mufit.pdf
    • http://poruzotosiku.getenjoyment.net/ceptam_7_notification.pdf
    • http://pogekoxuw.mygamesonline.org/85014842026.pdf
    • http://tiluvopira.medianewsonline.com/law_of_attraction_quantum_physics.pdf
    • http://auth02mobility.com/76193945999lqhaa.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://zipemoluligera.myartsonline.com/how_to_learn_dental_work_cost.pdf
    • https://dd39d194-9042-494f-90ab-223c96cf8da5.filesusr.com/ugd/5d3909_0cbf5cc20d6c41c482b7f9fbfa98a3ec.pdf?index=true
    • http://tuxefunuzire.atwebpages.com/resonate_nancy_duarte_download.pdf
    • http://banobozibijur.epizy.com/air_conditioning_system_in_aircraft.pdf
    • https://1138278f-e8d0-45ef-aef3-dbdd7428ac52.filesusr.com/ugd/5be868_e85f8011df814477b179a228ae602bd0.pdf?index=true
    • http://zogosugo.onlinewebshop.net/tijejaketekuf.pdf
    • http://bigamutalunu.atwebpages.com/julexivuzugixew.pdf
    • https://c4bedd8b-a3e9-4aa8-9751-a6fde4035b7e.filesusr.com/ugd/037f08_c39cd0ed9da54f7b94aae88a1eb96396.pdf?index=true
    • http://mopawok.epizy.com/project_closure_report_pmbok.pdf
    • https://ca39a19f-16f9-469f-ab0b-65ec0463b8d0.filesusr.com/ugd/cc9b97_59c076aa1e264840a5c08b9c503e3775.pdf?index=true
    • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000110a5.bin
ebc42dd65d6d82b6cd4a646eab17e6ba6266aa410ee2afdaae20b305c4a3b98e
pdf-font-stream PDF embedded font (sfnt) at offset 0x110A5 5612 bytes
font_01_sfnt_off000123ab.bin
8b0c9a0044eab96ae1200c913cddd5ebc68f2c47270bada9f89485826eafdb52
pdf-font-stream PDF embedded font (sfnt) at offset 0x123AB 10840 bytes