Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1631a47785aa363…

MALICIOUS

PDF

91.2 KB Created: 2021-07-03 22:41:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8d31d9e6d68c220ef7909321af4abd16 SHA-1: e5a16ec6cc46c1da35997cc7ef80f41e97daef4c SHA-256: c1631a47785aa3632ec983098c1b58a2baaca18880bf49abe8905365a22d82e8
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 WordPress sites or are part of link farms designed to redirect users. ClamAV and ML classifiers identified this PDF as malicious, specifically flagging it as a phishing trojan. The presence of multiple links to potentially compromised or disposable hosting suggests an attempt to lure users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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 https://baohohoanglong.com/userfiles/file/sutodomutofad.pdf In PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16087266e3b2f9---7781009747.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/d8bbae45b9666e3450a45ff702e5ab15/87173477677.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/lk9fsh934l81m7ev511633l9ge/xusiwopitukak.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160900d00ad147---neninoxubelexosamabovepe.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/visuvutexi.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a1f61b4d1---41610137181.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/3fe1e50b9754e9f76c2265339fb7f5c3/38360947654.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e40bbc5b05---98159156239.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/70d9f01393926f87d4dbb94cb694ad3b/59872399465.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab9a32358d0---38146619664.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd114da668---tonadegurifajopezeropago.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608e299bc77c4---jagugazozizukojotukajo.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/ca283c7a33bdb34fde79afcc1f9e9ffb/mutobudasawosuwomuzudoza.pdfIn PDF document text
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/b9a4f0e5fcdda2573ed7d970382a6317/438126136.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/2459d25de06bdb83e84593e6d7b7d3bb/61901784817.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aaa0018cd4a---13158632291.pdfIn PDF document text
    • http://deauville.ru/files/file/89993215293.pdfIn PDF document text
    • http://shacklefordlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/japenexuxepiwotug.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7abea94e3---losikebababarob.pdfIn PDF document text
    • http://unnatiwelfareorganization.com/ckfinder/userfiles/files/dubopulare.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/26090666384.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b3cd6ef34---finiminuravi.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0ab871a7f2---tolubemekesuruvivuvov.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=silicon+valley+show+castPDF 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_off0001009f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1009F 10568 bytes
SHA-256: 461bedabfc30e46c52b0c7a2088ae19a3b4df3eafc0c3bfe7a80f217b6d48ac9
font_01_sfnt_off000118ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118BA 17996 bytes
SHA-256: 85c4fd285a3edee997c0795c26833860a351b39ecc70ae6e7af4f966f83eb3bb
font_02_sfnt_off000147c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1