Malicious PDF — malware analysis report

Static analysis result for SHA-256 61100a780d6888b1…

MALICIOUS

PDF

72.2 KB Created: 2021-04-06 19:26:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: a153cd9376858ace797514247cdb9e32 SHA-1: a932eca6da6862ea1da98d23f29ff56994f647d6 SHA-256: 61100a780d6888b1865a1e35e03cb6f46aa17faf165b07e8b3da80e5e393a833
66 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a heuristic identifying it as a link farm on disposable hosting. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the nature of the embedded URLs suggests a phishing or malware distribution attempt, aligning with Spearphishing Attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 4

  • 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://zajinet.ru/strik?utm_term=central+vs+peripheral PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4481270/normal_5fd7a0f6dc697.pdfIn PDF document text
    • http://espaceabonne.com/34588052825tyiy3.pdfIn PDF document text
    • http://lalozakuren.66ghz.com/bse_midcap_index_performance.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366401/normal_5fe8e42ac8453.pdfIn PDF document text
    • http://xefatoge.iblogger.org/sexagadanegovugofemutopib.pdfIn PDF document text
    • http://tokio-2020.fun/wosomop93f81.pdfIn PDF document text
    • http://mixixokixa.22web.org/how_long_do_you_cook_a_half_ham_in_the_oven.pdfIn PDF document text
    • http://mirror-x.org/aadhar_card_by_aadhaar_number_online3q6tx.pdfIn PDF document text
    • http://instacopyrightcenter.com/sepupigorepevizntvo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449170/normal_6066c227955df.pdfIn PDF document text
    • http://otshelnik.net/851143616872057o.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480423/normal_5fcb52507c629.pdfIn PDF document text
    • http://wimutefeg.22web.org/49343123374.pdfIn PDF document text
    • http://bezufosaga.iblogger.org/free_bookshelf_plans.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://likikefiziz.rf.gd/bosque_seco_tropical_en_el_mundo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2edd81b-7cc8-4520-8d21-55fc947581e4/how_much_does_it_cost_to_fill_up_a_2008_honda_accord.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ddcd205c-57bc-4a30-ac12-992288b38ec9/breville_juice_fountain_cold_centrifugal_juicer_-_silver_review.pdfIn PDF document text
    • https://6a421494-2577-4416-904f-e17348f56b63.filesusr.com/ugd/85e76a_db5ab7707efd401892eb31ca918858f5.pdf?index=trueIn PDF document text
    • https://66f9544f-8325-470d-a543-c07714603334.filesusr.com/ugd/4b2642_9a53af3cea064fadb6cf81b15c54bb4b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/29804854-595d-41e3-a03f-8315b711d1d5/kemalikokawura.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d8aafc66-38f9-42bd-9860-caf1bd42524d/2015_jayco_redhawk_29xk_owners_manual.pdfIn PDF document text
    • http://marakolin.epizy.com/fupikawo.pdfIn PDF document text
    • https://b23183eb-b2e5-455e-bc25-91fac1efd10f.filesusr.com/ugd/cc14e4_26fb350cfa294517a9a110f88810b754.pdf?index=trueIn PDF document text
    • http://botujovibal.rf.gd/77269297081.pdfIn PDF document text
    • http://winuvifenam.epizy.com/double_digit_addition_and_subtraction_without_regrouping.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7d85279a-6805-44ce-8948-e6c15c53dde1/breville_800jexl_die_cast_juice_fountain_elite_juice_extractor.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A7 4668 bytes
SHA-256: d16bb30ca8e170e46a99a9154b013b5770388347327ffc6fb30f1d50ae16d382
font_01_sfnt_off0000e36f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE36F 9832 bytes
SHA-256: e0ff15285c953850a8b080404d73f47223923bea20c6b4111de6c89af69ad98a
font_02_sfnt_off000104fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104FD 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c