Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b982f040bc91b2…

MALICIOUS

PDF

82.9 KB Created: 2021-04-05 03:49:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 838a763bd3beeec6e5f5716145314d90 SHA-1: 56a3148d7b8714fc85564493773a8f4f2bd91706 SHA-256: a8b982f040bc91b287ca1909fc2612661d340609f768c7af71751b5f2b613906
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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 0.9998

Heuristics 5

  • 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 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/award?keyword=birches+summary+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4390057/normal_60687405ca35f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449009/normal_5fec6b0e2f0fb.pdfIn PDF document text
    • https://jofufibiwew.weebly.com/uploads/1/3/5/3/135347649/3381427.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370985/normal_603e733db0cc3.pdfIn PDF document text
    • https://bepixumute.weebly.com/uploads/1/3/5/3/135302933/vevebibetupekeni.pdfIn PDF document text
    • https://cdn.sqhk.co/xegunorasu/ijLRpbx/52925824398.pdfIn PDF document text
    • https://megidawuxuta.weebly.com/uploads/1/3/4/7/134729580/576354e3db2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467277/normal_60290da236802.pdfIn PDF document text
    • https://cdn.sqhk.co/wujakegu/gg5igFK/planet_earth_narrator_us.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391915/normal_5ffa4e6a54e4e.pdfIn PDF document text
    • http://zuduwipakeboku.iblogger.org/vozasi.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
    • https://uploads.strikinglycdn.com/files/2904c0ec-0aca-4bbe-8f61-694c2fa89e50/how_old_is_kaz_in_six_of_crows.pdfIn PDF document text
    • http://pemukusa.epizy.com/hakikat_pendidikan_agama_islam.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f612ab0-6d15-43ca-a551-729e35ba15a1/netgear_model_ex3700_setup.pdfIn PDF document text
    • http://novituwexuse.epizy.com/black_hole_formation_bacterial_takeover.pdfIn PDF document text
    • http://dibiremiva.rf.gd/george_shearing_lullaby_of_birdland.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_off0000fb6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB6B 5100 bytes
SHA-256: 58219658e9575da5fcb621fc4e432cb174321cb1b804fc380f319ab7187b98ef
font_01_sfnt_off00010cc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC6 10536 bytes
SHA-256: 215162a96ee22e0468f08dbc55f6095be91be2ca157401e8cb9464f41dfb75fd
font_02_sfnt_off000130eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130EB 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f