Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1a7ce997267d553…

MALICIOUS

PDF

138.4 KB Created: 2021-03-14 20:06:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: bf0cb83bceec316cc71f4bf66d00d1e9 SHA-1: 79c082fa7a7b3a81c7f5d923835ae3cbf98edda2 SHA-256: b1a7ce997267d5535f48f418387da5a820b68ed60b0ae1c2cd1d08c8251af86e
196 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which are part of an SEO link farm designed to redirect users to potentially malicious content, as indicated by the 'PDF_SEO_LINK_FARM' and 'PDF_SEO_UTM_REDIRECTOR_LINK' heuristics. The primary redirector URL, 'https://leonvi.ru/wix?keyword=gingerbreak+1.20+apk+download', suggests a lure for downloading software. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://leonvi.ru/wix?keyword=gingerbreak+1.20+apk+download PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4450418/normal_5ff096f53d298.pdfIn PDF document text
    • https://cdn.sqhk.co/xofozomuwef/inFihic/mix_3_colors_online.pdfIn PDF document text
    • https://cdn.sqhk.co/soxaxojuxa/jsiiaic/58550374999.pdfIn PDF document text
    • https://cdn.sqhk.co/lakodatoli/eihy97e/best_dth_recharge_offer_app.pdfIn PDF document text
    • https://cdn.sqhk.co/zewesifadeka/dBaBO7C/97204968825.pdfIn PDF document text
    • https://cdn.sqhk.co/puvegipuros/WrQogiq/walmart_online_grocery_shopping_promo_code.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447641/normal_5ff50a886276e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://0778d94d-b67d-49c3-8f6f-43f52d6edec9.filesusr.com/ugd/b85eb0_a79b8071c81a43ea956465a83ee69198.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/pipaneku/vodafojupelibadikegir.pdfIn PDF document text
    • https://s3.amazonaws.com/vaxebisapesi/full_time_what_does_it_mean.pdfIn PDF document text
    • http://fububosuvakosal.epizy.com/chemistry_of_aromatic_compound.pdfIn PDF document text
    • https://s3.amazonaws.com/xasovewipeje/star_wars_visual_dictionary_2020.pdfIn PDF document text
    • http://sedobuxekazadi.rf.gd/define_recapitulation_form.pdfIn PDF document text
    • https://s3.amazonaws.com/rutufokedizon/psoriasis_topical_treatment_guidelines.pdfIn PDF document text
    • https://e6c529cc-411f-4195-b5ea-7b5fd081490a.filesusr.com/ugd/b7ab08_f0b4c6d586684d3f969021a8aa6438cd.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/furunumaroxun/13414266224.pdfIn PDF document text
    • https://f7f2eb1f-4ce6-40bf-b337-6bcc2c9c1a95.filesusr.com/ugd/dc6899_ae4ee00d25ea40119716e9adb72cb5a3.pdf?index=trueIn PDF document text
    • http://gozipoxux.rf.gd/todajebidarajup.pdfIn PDF document text
    • https://97d49ff2-d914-4ae4-8ac8-5e5cf5f77cad.filesusr.com/ugd/6350c7_dbc52dc58768461ebf70d323404f29a1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kovibu/greedfall_ign_guide.pdfIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001bd08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BD08 5632 bytes
SHA-256: 3fbb1fbc65b988e24a9f80204384527e545703f5a88ffcb27277f07d83cbcaa4
font_01_sfnt_off0001d063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D063 17232 bytes
SHA-256: 61a4ebfee3959274cb7d5fb318c7780126600cca96fbd8d8918f40bf7bab76fa
font_02_sfnt_off00020654.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20654 16244 bytes
SHA-256: dc743b41e5c9b9e4d56ad8c22d1311c6eb3cecbc0d04401a7a33aeed2fa7944a