Malicious PDF — malware analysis report

Static analysis result for SHA-256 c87ffb0024b91ea5…

MALICIOUS

PDF

71.1 KB Created: 2021-09-21 12:50:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 45657caf1a72d76ff47df4971f23cb64 SHA-1: 1c3836b2cbd86be47022dd5e3ae14019c7dc07fe SHA-256: c87ffb0024b91ea54322e654d9b7d7f7f688b376ae18f4c4a8a3d6247924b62a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a large number of external URLs, many hosted on compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious or phishing sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely as a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pixomot.ru/uplcv?utm_term=league+of+stickman+warriors+mod+apk PDF link annotation
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/095a87h0t47otlr0jnp7dil3r5/nolijazikami.pdfIn PDF document text
    • http://wumag.pl/userfiles/file/xafexogisanigugabu.pdfIn PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/19295640287.pdfIn PDF document text
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/nuwanewunuwixadusipipe.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/5527498b6aceeb90a3c94443f4f06c2a/petogomanit.pdfIn PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/lowobukugimubabofajobubog.pdfIn PDF document text
    • http://lorichphoto.com/pictures/file/pujanifotuzematonefe.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/a7pmdje029nhv8gfs3imalp47d/kagikekuneboviwitizewog.pdfIn PDF document text
    • https://www.theoakshealthcare.com/my_content/js/ckfinder/userfiles/files/nutonojubejorudere.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/sadaminesemekusoninikug.pdfIn PDF document text
    • http://dcbestwings.com/uploads/files/futofagafa.pdfIn PDF document text
    • http://noithathoaphat11.com/upload/files/bubizelemusij.pdfIn PDF document text
    • http://agrobud.net/uploaded/file/gotuvoziduzuk.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/37190c151d3f3b967ef7eb245f5eaed7/safovudabujefobo.pdfIn PDF document text
    • https://clarkfamilybuilders.com/home/clark/public_html/ckfinder/userfiles/files/7416692240.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/59bbd21032d54b7d5d5e520e5d353bd8/wiwafutukuxuxenifalugenex.pdfIn PDF document text
    • https://madspot.dk/ckfinder/userfiles/files/1684100697.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///90442764109.pdfIn PDF document text
    • http://stillincontact.com/images/mails/file/43622210099.pdfIn PDF document text
    • http://riverla.vn/uploads/userfiles/file/dutizuloma.pdfIn PDF document text
    • https://www.domaine-de-la-ferme.fr/ckfinder/userfiles/files/20473526948.pdfIn PDF document text
    • http://bebelino.ru/userfiles/file/88453097817.pdfIn PDF document text
    • http://pk.mo/userfiles/file/wumesokesirimeg.pdfIn PDF document text
    • 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_off0000b48c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB48C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cca3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCA3 11152 bytes
SHA-256: d64e3757b08d9188a3c4ae7cdf323c78d3a031ca17d7e9e31f31aaca09e29d1f
font_02_sfnt_off0000e68e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE68E 15792 bytes
SHA-256: 5a7c5bf1d449b3b7c575d50e33a79984e3bb027c0bd1d15e40a1183b12a76329