Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1aa1e36f96525ec…

MALICIOUS

PDF

75.7 KB Created: 2021-09-18 03:52:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2884c186ab4bfff9f0c6d4ccaf20af36 SHA-1: b2f033b3ebfb08f7abe4852df2eb17b02d4ada6e SHA-256: a1aa1e36f96525ec5fb0bfdb02492ad174966a4556c19a9a731686d2e0475895
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting services, indicating a link farm designed to redirect users. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. The ML classifier and ClamAV detection further confirm its malicious nature, likely serving as a lure for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://ilkjv.com/Images/Media/files/lufig.pdf In PDF document text
    • http://www.ez4parcel.net/upfile/files/2021/09/16/zexal.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/0bd970bf105f76a7a15e367e4c1505bd/reroxojuxodune.pdfIn PDF document text
    • https://machinex-machines.com/UserFiles/File/75784595615.pdfIn PDF document text
    • https://siangyun.com/upfiles/editor/files/xijapetozogeguw.pdfIn PDF document text
    • https://meritumptt.pl/dokumenty/file/73843409900.pdfIn PDF document text
    • http://gamecoast.by/uploads/files/mavakawakejev.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/59567636329.pdfIn PDF document text
    • https://zemtechnika.lt/public/site/0files/94213879625.pdfIn PDF document text
    • http://umhouses.com/uploads/files/55912431032.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16143cc1b2c9ce---bimusuzuwunaritupagev.pdfIn PDF document text
    • http://mega-gold.com/userfiles/files/95646038007.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613032f02c895---jetonujumegomelu.pdfIn PDF document text
    • https://searchkar.com/ci/userfiles/files/8488378336.pdfIn PDF document text
    • https://monographie.com/ckfinder/userfiles/files/resexawi.pdfIn PDF document text
    • http://lica-mpt.it/userfiles/files/3987840836.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/zedobavi.pdfIn PDF document text
    • http://stl-hk.net/userfiles/gisagemewimegekibemafune.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/72845341331.pdfIn PDF document text
    • http://chrisdepanneservices.com/Sites/cds/files/tejakare.pdfIn PDF document text
    • https://presentkompaniet.com/img/content/file/30539950729.pdfIn PDF document text
    • http://npxbyy.com/wang3_3_10_27/Upload/Upload/file/2021921959133751.pdfIn PDF document text
    • http://npcbalkan.net/ckeditor/ckfinder/userfiles/files/88127740036.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=a7x+so+far+away+chordPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3E5 17620 bytes
SHA-256: f1aa3a1e757bc20c0356cb483996f99273f8621cf5023d3183040623eed69622
font_01_sfnt_off0000f127.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF127 10432 bytes
SHA-256: f33df553d1768950b8fe845f0860a22c6202ecdbde79fb7c41f14e284dbab65f
font_02_sfnt_off0001091e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1091E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1