Malicious PDF — malware analysis report

Static analysis result for SHA-256 5161dff3daddd635…

MALICIOUS

PDF

74.9 KB Created: 2021-08-02 16:22:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 5e18cbc71b9a632e4581d5467f810943 SHA-1: 1a4be2d8b2809a056d27013b4e5ceca201e52312 SHA-256: 5161dff3daddd635a2fca3003da647b7b5d101b0c8cc2d4c95d13d957db684f3
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated a high probability of maliciousness. Heuristics identified it as a link farm hosted on compromised WordPress sites, with numerous URLs pointing to potentially malicious content. The presence of these links suggests an attempt to lure users to external malicious sites, likely for phishing or malware distribution.

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
  • 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://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfb6bca3230---54675987937.pdf In PDF document text
    • https://www.apollopowersystems.com/wp-content/plugins/super-forms/uploads/php/files/9e27953453156d1af5d6a62bc937d8ef/gelimitifunibegomebo.pdfIn PDF document text
    • http://rc-modeller.se/images/file///vurozaromusizazeb.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/vidanisa.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f46d24b98---77862169933.pdfIn PDF document text
    • http://wjcopy.com/upload/files/37264448649.pdfIn PDF document text
    • http://firanywiktoria.pl/uploads/editor/file/xisolumasi.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/loxuxujukunufuxibit.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/34183922772.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/086d9ac402573f1be1ae23c522a1011a/99712223653.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/f6878dfd0827b7c8a6168856919dbf9b/buwitalin.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/uwedazijuvedinope.pdfIn PDF document text
    • https://fcksa.com/ckfinder/userfiles/files/82854682870.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/p2qd750li2d16i8ssmat4uu0es/73001150420.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/5f2c3e50f968635d017187c34026b53b/61172354183.pdfIn PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/51150078401.pdfIn PDF document text
    • http://com123.vn/uploads/file/78520987666.pdfIn PDF document text
    • http://smart-ventures.ch/upload/Editor_Images/files/tudazenisijevi.pdfIn PDF document text
    • http://leoclubmarsala.it/userfiles/files/mozurapel.pdfIn PDF document text
    • http://greenbrier101.com/userimages/gefapesulewijesiwoxur.pdfIn PDF document text
    • http://orderkiwicafe.com/uploads/files/34470174087.pdfIn PDF document text
    • http://hcvitamin.com/webroot/img/files/bopere.pdfIn PDF document text
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16084afbf74a59---ruzejadevuda.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=partes+para+molino+electricoPDF 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_off0000bfa6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFA6 10536 bytes
SHA-256: 1f1225674c63ab021298b7a36b6d7f90aaea10c90a6c94f6101c31d9f96742cd
font_01_sfnt_off0000d79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD79C 17480 bytes
SHA-256: bb28307b10ac95277759d70b800f502dea3e05f09fe799080b6b7ed1bb33230f
font_02_sfnt_off000103dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1