Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecfa3e80f0a0160c…

MALICIOUS

PDF

88.5 KB Created: 2021-10-12 07:11:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a74e77157ef4b0eef2fde0747c646f9f SHA-1: 75a4223154e3f696859b8e040e27f64dd338aa59 SHA-256: ecfa3e80f0a0160c30c296063496b18eb7ac85cafa0e3b57188d90cd3ad52ef2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised websites or disposable hosting, characteristic of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the nature of the link farm suggests it is designed to redirect users to malicious content, likely leveraging embedded JavaScript or other PDF exploits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://vnos.vn/app/webroot/uploads/files/13230474842.pdf In PDF document text
    • http://megalaserasia.com/upload///xiduzosimaxatowanoxajak.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/40130179991.pdfIn PDF document text
    • http://hyundaiokla.com/uploads/files/12492613660.pdfIn PDF document text
    • http://olymp-kiev.com/temp/fckeditor/file/9785556591.pdfIn PDF document text
    • http://saveursetsavoirs.fr/image/file/dabafewa.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/gopasozeram.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615137800d454---sowimop.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/a36edacfcac49ef756a9f9b8a3606961/854680717.pdfIn PDF document text
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/tizulop.pdfIn PDF document text
    • http://xn--80adib9cjd8a5e.xn--p1ai/i/upload/files/futafasobaregetanuxemad.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/16771c5cc362d2a571a7ea68730a817d/lamoga.pdfIn PDF document text
    • http://medicare-darmstadt.de/bilder/UserImages/file/68622905832.pdfIn PDF document text
    • http://baoveantam.org/upload/files/92767040078.pdfIn PDF document text
    • https://wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/33456070828.pdfIn PDF document text
    • http://yule-sign.com/upload/editor/file/20210919084404.pdfIn PDF document text
    • https://digireg.com/upload/tiwevisirujewadexex.pdfIn PDF document text
    • http://nitecoreromania.ro/files/file/93137601183.pdfIn PDF document text
    • https://gionggiacam.gagiongvitgiong.com/ckfinder/userfiles/files/kapuwafupokuputajuxabofa.pdfIn PDF document text
    • http://phayaotechno.com/UserFiles/File/23746396799.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/65dc92b61faa565b5fd6838d6ebe9e9e/26215191557.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/BcFPVxLj4jw/uplcv?utm_term=lord+of+the+manor+titlesPDF 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_off0000efa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA4 20656 bytes
SHA-256: 6e0d29cb81baaeaba96e3662a3213345e2bca9e8804a10cb16822afcf2356231
font_01_sfnt_off00012511.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12511 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013d28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D28 10576 bytes
SHA-256: a8151ce661071948712735b1d3fd9f96f12259ae9612370645301ce4f54f9f2f