Malicious PDF — malware analysis report

Static analysis result for SHA-256 280a7088eecd7b8c…

MALICIOUS

PDF

76.2 KB Created: 2021-04-18 20:05:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 0ba85a805c03a048dd977748362959a5 SHA-1: 1ddf42a85e2c659cbf10a0b1ef9eb7bb1b5d2f9f SHA-256: 280a7088eecd7b8c55d786fdc8c859695be938aaec72f199178bfb71a19aba65
174 Risk Score

Malware Insights

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

The PDF contains embedded URLs and heuristics indicate it functions as a link farm, with one URL specifically mentioning 'optiplex 755 video driver windows 10' as a lure. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic suggests the document instructs the user on how to handle a password-protected archive, a common tactic to bypass security scans. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://xajibur.ru/strik?utm_term=optiplex+755+video+driver+windows+10 PDF link annotation
    • https://tudadakamoziv.weebly.com/uploads/1/3/4/5/134596668/4944206.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459482/normal_603a51381b5fa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417644/normal_6048153f738c6.pdfIn PDF document text
    • http://options.expert/pusegakavojavaxsgg5b.pdfIn PDF document text
    • https://cdn.sqhk.co/banifiga/EidibYl/greatest_common_factor_worksheet_with_answers.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4422372/normal_5fcaff4649c7b.pdfIn PDF document text
    • https://cdn.sqhk.co/mibemofega/tjjjdjf/wixibodov.pdfIn PDF document text
    • https://vigoxanumevu.weebly.com/uploads/1/3/4/4/134466257/1548846.pdfIn PDF document text
    • http://socialwave.me/how_to_write_a_poem_about_yourself_in_third_personagyu7.pdfIn PDF document text
    • https://zogininofifus.weebly.com/uploads/1/3/2/6/132695288/024ae26f5c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471484/normal_6035783eb86bb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485313/normal_5fd28f2d01739.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://69f7c7ec-f776-4f8b-90c4-e8126cd531e3.filesusr.com/ugd/772020_6d01d98502af43569ef43a2c1edba021.pdf?index=trueIn PDF document text
    • https://b1b0174c-961c-4936-87f6-765e1132391e.filesusr.com/ugd/6cf804_7c1aa47da6f34cd7b8d4edb637277669.pdf?index=trueIn PDF document text
    • https://71a5d838-4e22-4830-8da1-7955ec3365f5.filesusr.com/ugd/f2f43e_443ecea79f92494d9d94204420651c90.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jimugivos/94359793447.pdfIn PDF document text
    • https://90ff81fc-98d9-4e53-96a3-aaa5c1c2042e.filesusr.com/ugd/bb5aff_8e49a426f4424b40a7b1b79bf5110a0a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xakusineba/61566939822.pdfIn PDF document text
    • https://s3.amazonaws.com/xapijifas/free_board_game_template_editable.pdfIn PDF document text
    • https://s3.amazonaws.com/bifamomove/e_aadhar_card_without_password.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_off0000ec02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC02 5388 bytes
SHA-256: 4b626903ff2cb836fe9a49d54d030d40d6520f9158136b52668b833894ea24aa
font_01_sfnt_off0000fe92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE92 10904 bytes
SHA-256: 74a98276801defa2929197a4330d2257ad47caa785f2adfc640e294e33927b5e