Malicious PDF — malware analysis report

Static analysis result for SHA-256 412d71ac7214ec4a…

MALICIOUS

PDF

88.4 KB Created: 2021-09-14 08:13:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7b3294fae69cb3d406b0d23d72d29777 SHA-1: 763f41777a3a027d1c5958a4c71441ce893d8736 SHA-256: 412d71ac7214ec4ab065d0ce3940936cba698f1333dd4b57374191cf19822107
164 Risk Score

Malware Insights

MITRE ATT&CK
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 link farm pointing to various PDF files hosted on potentially compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://playerpress.com/ckfinder/userfiles/files/38299189117.pdf
    • http://kemmurad.com/webroot/img/files/bonumitasimadep.pdf
    • https://ljlconst.com/admin/images/file/12079160962.pdf
    • https://toocapen.com/files/33027245405.pdf
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/fokixumakujesitedogenixe.pdf
    • https://norservis.cz/files/files/zukuwiferaxof.pdf
    • http://zjbfjt.com/upload/files/25212306672.pdf
    • http://files.ibiza-ferien.de/file/nolego.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/f600d5fd4dc441756c1c583f95999554/91961205113.pdf
    • http://orikon.net/Images_upload/files/vewezirimo.pdf
    • http://nessium.net/userfiles/file/nazulusosezoxujukogotevuz.pdf
    • https://easternresources.net/ckfinder/userfiles/files/loduga.pdf
    • http://nagakuratrading.com/js/upload/files/57098249467.pdf
    • https://mehreganimaging.ir/images/upload/files/25328250827.pdf
    • http://mulroyenvironmental.ie/userfiles/file/3934165197.pdf
    • https://mytopics.it/uploads/file/53236152629.pdf
    • http://isemya.by/modules/ariol/static/ariol/ckfinder/files/mipapagil.pdf
    • https://ienter.bg/files/dobulaketiwolit.pdf
    • http://adance0112.com/upfile/editor/file/naxijogixitudubukiwone.pdf
    • https://neksav.com/upload/ckfinder/files/91808314024.pdf
    • http://ssp.by/var/upload/deved.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/9rmh829nlnv5alonp8krkt5puq/33314228090.pdf
    • http://syarmarka.ru/userfiles/files/60711629384.pdf
    • http://ettermanenterprises.com/ckfinder/userfiles/files/75180280871.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/cb42a26c688cfa769098e8c38e3c971c/namilifogotimomimol.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=archon+extension+chrome
    • 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_off0000f4a4.bin
94d15831b6e7c4ba69f4987410e0ccb47ff41697df1e7d25678012f4b4c963a9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A4 10372 bytes
font_01_sfnt_off00010bef.bin
80e85b3175ae47f0014b46088fb22c26dba36b50b3b75c9cd5b678fa2899177e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BEF 18340 bytes
font_02_sfnt_off00013b80.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B80 16792 bytes