Malicious PDF — malware analysis report

Static analysis result for SHA-256 57dff17915c8d8dd…

MALICIOUS

PDF

90.0 KB Created: 2021-07-01 19:01:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8443595ff0ad007cff164f7d6e06c798 SHA-1: e30d0942a711cf6c7bbb94ca8e5adb1ebb77585c SHA-256: 57dff17915c8d8dd0ed399b59011fcc1d5a8f7f7c40cfa585132ad563058502d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 https://smidgel.ru/uplcv?utm_term=heart+pounding+after+drinking+alcohol
    • http://say-international.eu/userfiles/file/reborosagegoxafe.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/2ee49a4909ba6b7de362c2cfd614a46e/podajap.pdf
    • http://paillasse.hu/userfiles/file/49978796552.pdf
    • http://au-coeur-du-temps.com/userfiles/file/31232417767.pdf
    • https://sjalikave.hu/pictures/file/gubizejajepefaliker.pdf
    • https://skyzoan.com/cake/beta/userfiles/file/62726020879.pdf
    • https://webmenuplus.com/images/file/jajozinuko.pdf
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/3db256ioboucmmvvpcg50h76nc/merogajefabanikifuta.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a528558f6e3---74957589568.pdf
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e0d6e6cc6f---vikotajude.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b180d855988---83240654185.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2c82b24a7---92077363964.pdf
    • https://floresdeserrezuela.com/aym_image/files/10012455956.pdf
    • https://universal4shipping.net/userfiles/file/19087276961.pdf
    • http://101-games.ru/images/uploads/files/jidunejode.pdf
    • http://falerisztika.hu/tmp/bunaxabenevuxejome.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b46d383a2d0---8949205667.pdf
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/24636c414b914b4c8f4ecdf122a4086f/sasegebafako.pdf
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/60d52d041685c6d12332f1f6a58c7ef7/degepakusizokuruxazap.pdf
    • http://hieuchuan.com/upload/files/noxomutezutabexuwela.pdf
    • http://bayzones.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/15823771619.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bc339a02f4f---55079031576.pdf
    • http://brenna-ski.pl/userfiles/file/17535261234.pdf
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2869ee4ed2---76993098577.pdf
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608404ce0dcac---80711674492.pdf
    • http://am-assets.com/aom/magnolia/userfiles/file/5140827343.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f85c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF85C 16792 bytes
font_01_sfnt_off00011073.bin
a1d6609853e6e513e5947b915a6dc52eba02919b3ff81fa8d59d43569c0da583
pdf-font-stream PDF embedded font (sfnt) at offset 0x11073 10912 bytes
font_02_sfnt_off00012956.bin
9b86f01493b93d013078eb5bd1f76e7374c61e966ef6ea4fc6083423361061b0
pdf-font-stream PDF embedded font (sfnt) at offset 0x12956 18248 bytes