Malicious PDF — malware analysis report

Static analysis result for SHA-256 c434a9ab9f1a421f…

MALICIOUS

PDF

73.1 KB Created: 2021-09-10 12:15:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 63d0262c56c373266649dc9896fb0793 SHA-1: 26782806b967d01e6ca0a98e84671355d068218d SHA-256: c434a9ab9f1a421fe13dab0c277f97b28e28900133ddf081c7121fc39a830a76
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links strongly supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://drivingtesttips.ie/fckeditor/userfiles/file/92265186087.pdf In PDF document text
    • https://texasbordervolunteers.org/userfiles/file/samekijubazoderimela.pdfIn PDF document text
    • http://patrick-jardinage.fr/ckfinder/userfiles/files/18251452410.pdfIn PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/gupedemifazipujapiwal.pdfIn PDF document text
    • http://unitez.net/images/newtech/files/92630849071.pdfIn PDF document text
    • https://10kshot.com/customerinterview/ckfinder/userfiles/files/49294782443.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/6e86e8942c0bca3544948d7de2d27f34/netavikowusonagaj.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/gekonupamiv.pdfIn PDF document text
    • http://happy-land.hu/editor_up/79885352914.pdfIn PDF document text
    • https://sanghvicranes.com/staging/media/larenatinedute.pdfIn PDF document text
    • https://www.grdr.org/paidel/ckfinder/userfiles/files/xerozorulunanufid.pdfIn PDF document text
    • https://5ky13lu3-1251.com/contents/files/86251812084.pdfIn PDF document text
    • https://xn--fct5g39pjpo.tw/upload/leakstop/files/24537566485.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16134271369004---mokobowaletiramizutepa.pdfIn PDF document text
    • http://animalscipublisher.com/files/upfiles/file/rojadodiresegutelegek.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/d200363f1faede41175a0922c6d0cea4/gawetanopomarosolegema.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/gukazozobevabadafukulopef.pdfIn PDF document text
    • https://beruanglucu.com/contents/files/8116715139.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393d4f7a3fa---kobek.pdfIn PDF document text
    • https://unifor975.ca/userfiles/file/55462094637.pdfIn PDF document text
    • https://totspotdaynursery.co.uk/ckfinder/userfiles/files/babizanizak.pdfIn PDF document text
    • http://panova-art.com/files/file/vuvotezobezigikadar.pdfIn PDF document text
    • http://srub-servis.ru/userfiles/file/37056304015.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=mobdro+firestick+2021PDF 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_off0000b9df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9DF 10676 bytes
SHA-256: f4c9632814e51939df326137df98d30f23bb99c57188e9fdaf425eef5b400656
font_01_sfnt_off0000d292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD292 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eaa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA4 17472 bytes
SHA-256: 4f496c9637557ac9c3072f26636b3f71f88d603bd62d8734563458691beedc07