Malicious PDF — malware analysis report

Static analysis result for SHA-256 13fcd9e4f782b411…

MALICIOUS

PDF

123.0 KB Created: 2021-03-31 01:12:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 8eae12b0da2a5e9375ff3f6635c25dc0 SHA-1: edfd0bd85fd2e59403b51d08a597d2a5138ba1cd SHA-256: 13fcd9e4f782b4113d910ebb98db0451b5aed8527a69fd5dbc9d68195fcdee3b
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting services, suggesting a link farm designed to distribute malicious content or phish users. The heuristic 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a large number of links, with one prominent URL being 'https://midufefew.ru/award?keyword=ayushman+bharat+bimari+list+pdf+download'. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://midufefew.ru/award?keyword=ayushman+bharat+bimari+list+pdf+download PDF link annotation
    • https://xusezazidajitov.weebly.com/uploads/1/3/5/3/135325201/4997670.pdfIn PDF document text
    • https://wimiwimevodozaz.weebly.com/uploads/1/3/0/8/130874111/3501161.pdfIn PDF document text
    • https://zewabezasakaru.weebly.com/uploads/1/3/4/5/134593707/zemagulivivojuvov.pdfIn PDF document text
    • http://dowapid.iblogger.org/83969842594.pdfIn PDF document text
    • https://varepanuror.weebly.com/uploads/1/3/5/3/135394497/ae583facfb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • http://kikisitakas.rf.gd/88392762.pdfIn PDF document text
    • http://gixosuwali.rf.gd/aeroflot_russian_airlines_flight_information.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/55ef2480-e27d-4214-8e48-2da935222175/32697508888.pdfIn PDF document text
    • https://e05653fc-386e-4c8b-889d-738aee72c63e.filesusr.com/ugd/62421a_6ac296d169ec4083a96f408b75957b68.pdf?index=trueIn PDF document text
    • http://joxowosikaze.rf.gd/9643978279.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/accbdba0-98fc-4673-8824-f90bbf01a2f1/kobigupezubelo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ebdbd96f-54ef-4afc-811f-3792395623eb/what_does_the_orange_room_symbolize_in_the_masque_of_the_red_death.pdfIn PDF document text
    • https://8f1c0ae7-1ba6-4c51-a623-4d29f5e3aebb.filesusr.com/ugd/c1615c_389af61f69c04584bbfda144e91c5a57.pdf?index=trueIn PDF document text
    • https://ce55c564-0e79-48ac-bd91-a034cff8554b.filesusr.com/ugd/bd1fc0_57bc483e77ba46e0a656e436bca0140c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/eede3653-cee6-41eb-bb15-a8a9aaf10452/when_dimple_met_rishi_summary_ending.pdfIn PDF document text
    • https://45f91bdd-2b68-4e60-ae2c-b14373ae5332.filesusr.com/ugd/0d089b_65b1b4314eb9480fad9e79f68df89686.pdf?index=trueIn PDF document text
    • https://05efeaee-ea5b-4dc8-bddc-a5098cc0dcbd.filesusr.com/ugd/c06c30_6c3bcaaaf19541e5862abc245e1318f4.pdf?index=trueIn PDF document text
    • http://xazitew.epizy.com/answering_machine_meaning.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c76152e3-21b1-4c97-af96-7d8ad484e051/43254474840.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c93981d3-0bca-424c-a051-e3be1de6bff9/sword_art_online_vr_gameplay.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c01b2dd-4345-4f78-818a-85f2af6e8271/black_and_decker_3_cup_rice_cooker_instructions.pdfIn PDF document text
    • https://2eda13a9-9e0f-47dd-bbfa-a9a5028a3314.filesusr.com/ugd/61c57f_e067db12d0a14a19976d86f3df2ad2c3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/896d3615-2ead-4696-931a-e00ad1f2a4ae/how_to_read_a_graphic_novel_lesson_plan.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://www.geocities.com/mitra_anirban/hobbies.htmGNUIn PDF document text
    • http://www.gnu.org/copyleft/gpl.htmRegularIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015ec7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15EC7 5604 bytes
SHA-256: f6076768e9daf68ec81539fdbc558f93fabd6e8499870502a4a4f66b7ba42475
font_01_sfnt_off000171b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x171B4 3720 bytes
SHA-256: d5ecec3e822993868ba70e247019bcdb656a9fee58d620eb93bc70658e929280
font_02_sfnt_off00017d17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D17 10212 bytes
SHA-256: 4dce1bfb8136226271123664d5b0335704411eb23694f79641415758f61afbe3
font_03_sfnt_off0001a065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A065 20612 bytes
SHA-256: 213dfce1b114270109cd7224470179accb4b2fab38ff87b845853a2150a8a24b