Malicious PDF — malware analysis report

Static analysis result for SHA-256 12b3839fe7075629…

MALICIOUS

PDF

75.4 KB Created: 2021-03-05 10:41:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 041834bf3bfa34027b480cf6163b90ac SHA-1: b53a7cc7b6a947cf3b1b95a3eb2f66a5b08ab261 SHA-256: 12b3839fe70756294f57957c9ac91280b44a4283d5390bc97658c14cc744c379
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many of which are hosted on disposable domains, indicating a link farm or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The document body, though heavily obfuscated, contains references to 'coupons' and 'wkhtmltopdf', suggesting a lure to disguise the malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://seumenha.ru/123?utm_term=burger+king+printable+coupons+july+2020 PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4419633/normal_6004f6ad254ff.pdfIn PDF document text
    • http://funapuz.iblogger.org/early_civilizations_chart.pdfIn PDF document text
    • http://ripuxojelirul.iblogger.org/67341515647.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419832/normal_5ff3a9fce2589.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486213/normal_6015b6aa74aa0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367921/normal_603fb3c905c87.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479715/normal_601d941b72582.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/falejogajir/ace_certified_trainer_salary_in_india.pdfIn PDF document text
    • https://e8dc5420-792a-4861-90db-09cfc8d8a7d1.filesusr.com/ugd/1378f5_493c3504c58a4eb990381a5244ddfeba.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kabisebax/aankhon_ki_gustakhiyan_video_song_hd.pdfIn PDF document text
    • https://933527c5-e005-4225-a3aa-05fee46c7696.filesusr.com/ugd/b51dd5_d1e14fc453064e409eb8fb7706e936e2.pdf?index=trueIn PDF document text
    • https://59e5a08b-0d8d-455f-a3a7-35a3b781ab3e.filesusr.com/ugd/784815_89c0cdd84ed346e69742825fee164035.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d832a33-d169-40a5-a580-b04b8f180729/xawatavir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2d15b9a2-75eb-461b-81c4-8e56cc996310/94421790235.pdfIn PDF document text
    • https://f37c3615-20b0-4e70-b1e7-2acf34113780.filesusr.com/ugd/1e533a_9d8783d4ea4d489090a911952323520e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dobikasukavu/84972778256.pdfIn PDF document text
    • https://a581e706-3bf6-41fb-8978-ad4d4077590d.filesusr.com/ugd/afbe6b_1f2bde45cacb42e59012c900dda523cd.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/posufij/ansi_c_programming_language_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b45453c1-2c08-4139-a763-f8532d746ced/thank_you_mom_quotes_from_daughter.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5b31a1c1-33e7-4661-8b92-d43840077210/the_river_cafe_pearl_river.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/097062c1-4607-406b-8389-8c04cca531cf/waxuvijojopalewamovap.pdfIn PDF document text
    • https://329f26c8-0235-4118-8622-173d264d9cf1.filesusr.com/ugd/221f3a_84f3f6457a5642e5a5a92b0c57ee1534.pdf?index=trueIn PDF document text
    • https://e05653fc-386e-4c8b-889d-738aee72c63e.filesusr.com/ugd/62421a_275b8600ee5c4c2aaca00f058cfd7244.pdf?index=trueIn PDF document text
    • https://729282ec-1290-4cbc-9302-cf8a24acd4c7.filesusr.com/ugd/42c189_dc2626197134411bb0df41a69e85928a.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e687.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE687 5804 bytes
SHA-256: bb4a6485644a861f3465c064bafb2775abd66b312d20fc861105ab846817c938
font_01_sfnt_off0000fa6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA6E 11008 bytes
SHA-256: 3a64fc802438401dc6790488a6887fd205d65d6372b611163e932d08331625ac