Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8a578435c964a74…

MALICIOUS

PDF

80.0 KB Created: 2021-04-06 21:09:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 88d8c33361c54e3e49014a07a4be173c SHA-1: 9f515f629e0b5570368ce9c40884400aa2601f4d SHA-256: a8a578435c964a74e224eb83a07726c35daf15196dbac03d17fefe61a0545c6c
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://mezovuduw.ru/123?utm_term=coles+bread+nutritional+information PDF link annotation
    • http://nafuvexozoli.iblogger.org/hague_apostille_convention_1961.pdfIn PDF document text
    • http://goxivomibivufuv.mywebcommunity.org/are_hearing_aid_domes_made_of_latex.pdfIn PDF document text
    • http://bitalotava.scienceontheweb.net/relewebomujurijaforoj.pdfIn PDF document text
    • https://wokawopirajer.weebly.com/uploads/1/3/3/9/133999547/bukenuzodabuwuf-wisidow.pdfIn PDF document text
    • http://najapizarut.22web.org/doxepufujetejuf.pdfIn PDF document text
    • https://fenawivo.weebly.com/uploads/1/3/4/0/134000055/detosugawafel.pdfIn PDF document text
    • http://likefetevu.getenjoyment.net/bromwich_integral.pdfIn PDF document text
    • http://vosajizegek.mypressonline.com/87273273343.pdfIn PDF document text
    • http://walabakubu.iblogger.org/auriculoterapia_oleson_gratis.pdfIn PDF document text
    • https://kovexinuzik.weebly.com/uploads/1/3/0/8/130815277/fbad6a3d1f380.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://2a4065d7-883d-43e8-a524-7ce9aa4b4e88.filesusr.com/ugd/ccb1c6_d86138cb1c494fce97ba62f276045a13.pdf?index=trueIn PDF document text
    • https://a3c35cc3-4a3f-4d41-ab51-8b3e4b114d30.filesusr.com/ugd/2b25b5_33cec431848a405eb3e8928bfe7ae51a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sorapobuk/aluminium_gas_welding.pdfIn PDF document text
    • https://938a05da-450f-421e-a59b-0448473a402a.filesusr.com/ugd/cb5dea_944dca0a60f14bad9c20affe812c7bd3.pdf?index=trueIn PDF document text
    • https://1639490a-f715-481e-9fb1-af38d332269b.filesusr.com/ugd/a59130_4fd2963af55d4e6aafbfa9184e445075.pdf?index=trueIn PDF document text
    • http://vijanemafe.rf.gd/blackbird_ukulele_chords.pdfIn PDF document text
    • https://650c977b-0274-48a2-8498-43c0efc39f4e.filesusr.com/ugd/dbad32_ded66166c1974753b2cfd358e616a9ae.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/pibajuwi/how_to_use_a_keurig_mr_coffee.pdfIn PDF document text
    • https://s3.amazonaws.com/sefabe/dudezubikeziv.pdfIn PDF document text
    • http://gixejemazob.myartsonline.com/ejercicios_alcanos_alquenos_y_alquinos_resueltos.pdfIn PDF document text
    • https://8459f3b7-b2e6-4b58-af31-5f29adf293b7.filesusr.com/ugd/a68450_99f30b5d6b1246bcb32c088d1999b0c5.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/saxefi/pro_forma_statement_is_used_for.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f92c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF92C 5096 bytes
SHA-256: 7259370bc06066585df3eb27e26b1b52be02c08e481de4c0c622d6287261c23e
font_01_sfnt_off00010a5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A5F 11884 bytes
SHA-256: ae97ed34be4f9ceab46484b346d47de9fd53c69023276685e2b794766a1e1f16