Malicious PDF — malware analysis report

Static analysis result for SHA-256 39fe1f7583e72a34…

MALICIOUS

PDF

78.9 KB Created: 2021-03-10 19:58:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 5d94b80a649fc07c0613c3f7c5503c35 SHA-1: 5cbac3f2f5145881470e77ee9525b798a8569b57 SHA-256: 39fe1f7583e72a345dd84f2a0dde02bd2fc408b201f90f98521db36e595a5753
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 pointing to disposable domains, suggesting a link farm or phishing operation. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a spearphishing attachment designed to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • 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.
  • 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://maypoin.ru/123?utm_term=biosynthesis+of+purine+pdf PDF link annotation
    • https://cdn.sqhk.co/nasanoroge/gjieBgg/xozunamotu.pdfIn PDF document text
    • https://cdn.sqhk.co/gisepavuv/aXjeWjc/zombie_land_rush_apocalypse_roadkill_3ds.pdfIn PDF document text
    • http://tufodudem.mypressonline.com/simple_pencil_drawing_ideas_for_beginners.pdfIn PDF document text
    • http://nodozavi.iblogger.org/in_play_store_whatsapp.pdfIn PDF document text
    • http://faketikus.22web.org/65484724667.pdfIn PDF document text
    • https://cdn.sqhk.co/zepipawetopi/eBjeJhd/transformers_shattered_glass_fanfiction_starscream.pdfIn PDF document text
    • http://golivexi.22web.org/fuxemofunidowugubovaxezed.pdfIn PDF document text
    • http://vowufijetapiko.sportsontheweb.net/how_to_replace_a_flame_sensor_on_a_lennox_furnace.pdfIn PDF document text
    • http://pewekelexu.mygamesonline.org/causas_del_embarazo_adolescente.pdfIn PDF document text
    • https://cdn.sqhk.co/pujigaloruri/jf4iaRa/cute_puppy_wallpapers_for_desktop.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://f1c0478e-57b3-422a-b8eb-433964b677d2.filesusr.com/ugd/16c17d_bc40cad4aee24594bd24acab0ea20234.pdf?index=trueIn PDF document text
    • https://1416a32c-f91c-4ec3-9c10-bfdf610c7df7.filesusr.com/ugd/76de1a_6251c9660f8342638a07ab903996f0b0.pdf?index=trueIn PDF document text
    • http://nudifezidezi.rf.gd/bogedogejejak.pdfIn PDF document text
    • https://2cfcb734-ec62-4cd9-b61c-03d4762ad765.filesusr.com/ugd/a891c0_c167207318704a30b50352a8dfe180f3.pdf?index=trueIn PDF document text
    • https://17c3d818-7f64-4152-976a-2fa997d7a7be.filesusr.com/ugd/e2c250_4ea870f9f5f34268a27a9b92bcd75bd9.pdf?index=trueIn PDF document text
    • https://748f1d53-d141-46c1-926a-d14fc69713a3.filesusr.com/ugd/e3ed1f_7556a55046704a82bd492f5b8ebebd8a.pdf?index=trueIn PDF document text
    • https://09235f31-469a-4613-94fc-36d04c1f642a.filesusr.com/ugd/8b6407_8be0483e5be7485dbbf32c7d39681dc0.pdf?index=trueIn PDF document text
    • https://8b7199fc-a029-4910-8138-caee300d1cbd.filesusr.com/ugd/da8f68_685e390db5e445dfb3be134ce4a48e96.pdf?index=trueIn PDF document text
    • http://risepaxazitomep.rf.gd/adding_integers_on_number_line_worksheet.pdfIn PDF document text
    • http://morufigalolo.rf.gd/todas_las_aperturas_de_ajedrez.pdfIn PDF document text
    • http://kubomefewofumim.atwebpages.com/gukaguxamo.pdfIn PDF document text
    • https://fd0ef26f-7b8f-4c91-b3b2-19f7ec93487a.filesusr.com/ugd/4174bf_b59e60fe932142efb7524c5ef592d10e.pdf?index=trueIn PDF document text
    • https://5b3500e9-40b4-440a-9ada-171ed8bcf4c9.filesusr.com/ugd/7820d0_a78acb621a984c4294dab7f0a8858c77.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_off0000f74e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74E 5036 bytes
SHA-256: 92e91af98bc98bec53b547117c3c44f260829a52a532bf549577b68bc34d5e71
font_01_sfnt_off0001087a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1087A 11188 bytes
SHA-256: 2a54ccbc8e380c063423b633b8ef99f8189786f4323bd78c19944ab6939b9c1d