Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7eef4d5eca9d958…

MALICIOUS

PDF

80.7 KB Created: 2021-06-01 17:16:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a9eb337215d859a7d81deb21771ce3f7 SHA-1: 7861d9de04424cd4abefa949b714542670b6ad6d SHA-256: c7eef4d5eca9d958b7e0e43170d2eeba4331b4fed67e0c2a7223f7ffe1d71423
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 hosted on disposable domains, suggesting a link farm or SEO spam operation. The document body, though heavily obfuscated, contains references to a game walkthrough, which is likely a lure to attract users to click on the malicious links. ClamAV and ML classifiers also flagged this PDF as malicious, indicating a high likelihood of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • 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.
  • 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://medvor.ru/pbw?utm_term=skyrim+being+a+cow+walkthrough
    • https://repiwolaz.weebly.com/uploads/1/3/1/3/131381539/mevel.pdf
    • https://nigomisenavuluw.weebly.com/uploads/1/3/6/0/136095850/bibawexi_nekugi_wavupobomel_sevotupabowos.pdf
    • https://zeleveruki.weebly.com/uploads/1/3/4/8/134898901/pupitonefarages-jiwewakerej.pdf
    • https://jurogewogil.weebly.com/uploads/1/3/4/3/134318518/bagivumobesen.pdf
    • https://didirivex.weebly.com/uploads/1/3/4/2/134265945/gevani.pdf
    • https://vunatoja.weebly.com/uploads/1/3/0/7/130738644/24fc6fac180d3.pdf
    • https://ginubeputugexow.weebly.com/uploads/1/3/0/7/130738710/bb147ee2.pdf
    • https://movekepuvixoma.weebly.com/uploads/1/3/4/0/134041071/3575040.pdf
    • https://panulozeti.weebly.com/uploads/1/3/5/3/135351273/2a57fafdab5.pdf
    • https://kaxukododeregoz.weebly.com/uploads/1/3/0/9/130969338/lurekozibomixi.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://supijexed.pbworks.com/w/file/fetch/144446037/free_printable_coordinate_graph_pictures_worksheets.pdf
    • http://zekodunu.pbworks.com/f/how_to_make_crosley_record_player_work.pdf
    • http://kipizasuzeda.pbworks.com/f/bepozajogudiwuzina.pdf
    • http://zeladejan.pbworks.com/f/30050319288.pdf
    • http://xedidovetaw.pbworks.com/f/lista_de_exercicios_multiplicao_e_diviso_com_numeros_inteiros.pdf
    • http://wejojixi.pbworks.com/w/file/fetch/144423687/fidelity_net_benefits_phone_number.pdf
    • https://uploads.strikinglycdn.com/files/76bea8c1-33aa-4692-b85e-478983b3f113/are_vogue_cigarettes_good.pdf
    • http://xorunezagu.pbworks.com/w/file/fetch/144460995/how_much_protein_to_eat_on_hcg_diet.pdf
    • https://uploads.strikinglycdn.com/files/b9f6603e-a40c-4005-aa76-0a32b00dbb75/pewisige.pdf
    • http://fisukafetif.pbworks.com/w/file/fetch/144424947/khalil_gibran_livros_em.pdf
    • https://uploads.strikinglycdn.com/files/37b643df-9712-4461-bebf-8f2eb643c623/trollface_quest_3_unblocked_games_77.pdf
    • http://niwomif.pbworks.com/w/file/fetch/144427749/imprimir_talon_de_pago_jubilados_y_pensionados_issste.pdf
    • http://wefolevemud.pbworks.com/f/56804698314.pdf
    • http://kufogokoges.pbworks.com/w/file/fetch/144463047/comprehension_passages_for_class_12.pdf
    • http://xuresasadox.pbworks.com/f/how_much_does_drywall_finishing_cost_per_square_foot.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
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5e0.bin
9281ac385e06ada28119de2d56339e13f0ce185dce09596e5129751aa1207b7a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5E0 5536 bytes
font_01_sfnt_off0000f8aa.bin
baf785caf1d0edf29bb37a48c1f4c25306d75ab7717a303b1b71f634e4ed809e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8AA 10356 bytes
font_02_sfnt_off00011b7c.bin
33b90bbcff73dd6910ee4227553d1232aac8839fa0467d0b6e4d1c495f3c4171
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B7C 17380 bytes