Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8997fe0857bcebf…

MALICIOUS

PDF

77.9 KB Created: 2021-07-25 14:32:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 89eed4a7d36a5483cda0bdacc417cd2b SHA-1: 8cfe84b3cb4483b5d5bac1b5984bfc9ac3fc57b7 SHA-256: c8997fe0857bcebfcd06072a8d3fdfa60a01789261c973b1ae392e8569e3531d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a downloader or redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://sk-uralstroy.ru/uploads/files/41458191861.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/grb4fpobkltasqa0qmvis097vc/gelodububoriw.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/imisgrbcogm4gsi4qhgkcvjr4h/18641976479.pdf
    • https://floraplant.gr/FCKeditor/userimages/file/47352123828.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/164e64f7c748f15a8e647c8753a55875/sowanuwokutepuzerimarer.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16096784a90041---jozeravida.pdf
    • http://kozszemle.hu/uploads/files/97892774283.pdf
    • http://ankurgroups.com/userfiles/file/sijimiwizatejobuwavirugun.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/7ed0737b3f73a7f105d1bbaecf5f5c33/fomababesexow.pdf
    • http://ylpqzl.com/ckfinder/userfiles/files/bapebudutape.pdf
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/9a42c496286fd87bd038208a04f2bd1b/62576478396.pdf
    • http://xedaptheduc.net/app/webroot/uploads/files/nenekumirut.pdf
    • http://www.allatpatikapecs.hu/images/file/70611282249.pdf
    • https://theelementrama9.com/userfiles/files/zixito.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0ef922435dbd06ce83d2dc857e88bc60/tewoxex.pdf
    • https://planet-for-events.de/userfiles/file/wutofag.pdf
    • https://gites-les-bardots.com/userfiles/file/58749177973.pdf
    • https://rachelrom.com/rescontent/file/82659929920.pdf
    • https://haysalon.com/public_html/userfiles/file/67023881949.pdf
    • http://harc-ias.vn/Images_upload/files/39506511829.pdf
    • http://kaupa.cz/userfiles/file/46632280940.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/a8uu3hgia726ghrqsse1rshqsl/pelataxutotip.pdf
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/0acscprnkk1f9ka4590bn9ki50/vuziwuvivikados.pdf
    • http://woodwork.pl/ubezpiecz/obrazy/file/24242912897.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=nise+control+systems+engineering+7th+edition+wiley
    • 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_off0000c952.bin
934d88bc0a898ea21e9f60763274982c0d265ce730fde00a2fe318febf498b1a
pdf-font-stream PDF embedded font (sfnt) at offset 0xC952 10880 bytes
font_01_sfnt_off0000e22b.bin
d6a91c5415e1c37098529a5f1ebe4c37d992b90156344ab1703492e954c8c8ce
pdf-font-stream PDF embedded font (sfnt) at offset 0xE22B 17632 bytes
font_02_sfnt_off0001104e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1104E 16792 bytes