Malicious PDF — malware analysis report

Static analysis result for SHA-256 a91be8f3bc446325…

MALICIOUS

PDF

84.4 KB Created: 2021-05-15 00:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 4c864640d877f38a05a17794757e21b6 SHA-1: 2a636330a8f456a8c66c9e1ad620ad44943bef72 SHA-256: a91be8f3bc446325dab55ac9c63530794afede79f68557fcf52381a28d01b5ba
196 Risk Score

Malware Insights

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

The PDF file contains a heuristic indicating a link farm and a redirector, suggesting a phishing or scam attempt. The embedded URL `https://jottigo.ru/strik?utm_term=how+to+tell+a+guy+isn%2527t+interested+in+you` and the linked PDF `https://cdn.sqhk.co/jifexekezeli/ijjc92h/anxiety_and_defense_mechanisms.pdf` are identified as potential IOCs. The ML classifier and ClamAV detection strongly indicate maliciousness, likely related to phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://jottigo.ru/strik?utm_term=how+to+tell+a+guy+isn%2527t+interested+in+you PDF link annotation
    • https://cdn.sqhk.co/jifexekezeli/ijjc92h/anxiety_and_defense_mechanisms.pdfIn PDF document text
    • https://cdn.sqhk.co/zenekukera/jjd8rje/guide_for_forza_street_pc.pdfIn PDF document text
    • https://cdn.sqhk.co/xegunorasu/iejcwhj/88005245292.pdfIn PDF document text
    • https://cdn.sqhk.co/jinavefajevo/jdjiXgi/zuraxo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386366/normal_5fdc52ea63e66.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4443598/normal_60066095e4fc6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369771/normal_604cc1cb446b7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379241/normal_5fe939e6a6fee.pdfIn PDF document text
    • https://cdn.sqhk.co/molavagew/gcznIji/bazefurepomod.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499972/normal_5fdbe6586df7f.pdfIn PDF document text
    • https://cdn.sqhk.co/tovipovo/WgfQ3tN/29199862538.pdfIn PDF document text
    • https://cdn.sqhk.co/rolidazi/aIje3hj/aaa_login_illinois.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/498498f8-27fb-4a0f-83e9-720a146de7c8/petujifiralodujunenifa.pdfIn PDF document text
    • https://s3.amazonaws.com/wazotojemov/tactical_self_defense_classes_near_me.pdfIn PDF document text
    • https://dec4a425-646e-450a-80ca-a73a75d058ad.filesusr.com/ugd/ba3095_2be6ebe89e014e5ca2c1582c3bb9eb97.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/64802609-5de6-4771-adad-86bb9df46a8f/linux_shell_scripting_tutorial.pdfIn PDF document text
    • https://s3.amazonaws.com/sakaburepagase/dog_man_fetch_22_trailer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5562647b-c099-4680-8e91-5e61c86d8bd4/rimeponaxavo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/24fd2768-033d-4fe7-8efe-01715261adb6/why_is_my_fellowes_shredder_not_working.pdfIn PDF document text
    • https://s3.amazonaws.com/vavapekadoliti/27315983947.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4b553289-e60c-4ab7-b7a0-d3496a6d5153/19544857998.pdfIn PDF document text
    • https://s3.amazonaws.com/jadere/supavifazuferupuditero.pdfIn PDF document text
    • https://s3.amazonaws.com/jiwisigetizoxif/buzuxeke.pdfIn PDF document text
    • https://d1159ab4-cbf5-42eb-897b-83a5e94cd7da.filesusr.com/ugd/536122_3bc5c650180246fcb1108c8c5112cce1.pdf?index=trueIn 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_off00010b0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0F 5180 bytes
SHA-256: 07ebc69035df477696f4a22b39ce550add193b84519c41ca6841a061e50abccd
font_01_sfnt_off00011cdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CDB 11016 bytes
SHA-256: e9fb43ff05b91db4e352eb649b9616a03222a37214e112c5eeb99dd6da816c76