Malicious PDF — malware analysis report

Static analysis result for SHA-256 33e139e12bee9359…

MALICIOUS

PDF

72.9 KB Created: 2021-09-21 12:17:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 80b8a2244a9ea85c83b89b24bc35628b SHA-1: d75016d6231d9d9f477a92f88a307e92cdf723e9 SHA-256: 33e139e12bee93599afff8e7c20332526162da0737e2b189164c1af4f1e2a88a
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several pointing to compromised WordPress upload directories, indicating a potential distribution point for malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, but the structure and URL analysis point to a link farm designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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=chrome+anti+adblock+killer PDF link annotation
    • https://lomasdelaweb.com/userfiles/2008.09/file/jegatevejelel.pdfIn PDF document text
    • http://automag.pl/userfiles/file/73154159420.pdfIn PDF document text
    • http://bjbtrh.com/files/pic/file/9408398702.pdfIn PDF document text
    • http://heizler.hu/files/file/11707824421.pdfIn PDF document text
    • https://webrobogo.hu/kepek/51623347771.pdfIn PDF document text
    • http://virtuozi.ru/sites/all/sites/virtuozi.ru/files/fuzujikonivef.pdfIn PDF document text
    • http://kleinschadenexperte.com/userfiles/file/62854175127.pdfIn PDF document text
    • https://b2cexpressdemo.com/userfiles/file/lovegetigi.pdfIn PDF document text
    • http://studiomontironi.eu/userfiles/files/15035202268.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/33012790647.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/9bf49b31e3ff70d2324013f4b02d5298/4782943968.pdfIn PDF document text
    • http://52fotki.ru/ckfinder/userfiles/files/fezisujumidujokepun.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139fe1cc427c---pikuxobusugavopofitif.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/wawageperukogoboxulo.pdfIn PDF document text
    • http://hytechplus.com/userfiles/file/sifadadujilixumimukomadaz.pdfIn PDF document text
    • https://nedimgame.com/calisma2/files/uploads/1844517739.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/bawoxoj.pdfIn PDF document text
    • http://ducthanggroup.com/webroot/img/files/wewujotumonadotomijizida.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/nuf48pjgjrjrau0272l650a45j/dudawerazodimekojasugof.pdfIn PDF document text
    • http://mptech.vn/ckfinder/userfiles/files/38476759632.pdfIn PDF document text
    • http://satthachkhe.vn/image/file/tonazofem.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_off0000b97c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB97C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d18e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD18E 16948 bytes
SHA-256: 5578f1fc49cd756c161e7532540ff020ebb8cd070aa4f787ed3ce86728435dbc
font_02_sfnt_off0000fd62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD62 10728 bytes
SHA-256: 4223bda8cc1444867260b1be5084b069cea802fcd50d1ede9daabcbe6e04b919