Malicious PDF — malware analysis report

Static analysis result for SHA-256 39e8154e2995fbe8…

MALICIOUS

PDF

104.0 KB Created: 2021-07-27 03:08:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8ac9e32d3b7a79b81001a755feb7cbf6 SHA-1: abfd988f91bf6006a382c9ede03e7c34d92c6a20 SHA-256: 39e8154e2995fbe8ebf4c78ff8dcf16098f7588ce6ecaf098bdb57b2ccb0a836
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. It also features a large number of external links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to distribute malware or redirect users to phishing sites. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6eef367880---34033556396.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cafbaa2274---78277121970.pdf
    • https://akapacha.com/userfiles/file/satunamo.pdf
    • https://sofanet.ro/ckfinder/userfiles/files/55244634099.pdf
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eed45b5301---55094373267.pdf
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/m4tf191838t972lb0kocv6ijv1/xolerubowifivozoreba.pdf
    • https://reaga.net/js/ckfinder/userfiles/files/68924909873.pdf
    • http://maility.pl_adresuserfiles/file/17064701734.pdf
    • http://rw-hse-businessconsulting.de/userfiles/file/37916364181.pdf
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/fd5dfb309214528f6f298d4c966362a5/35146461459.pdf
    • http://monterroso-construpuntos.com/campannas/file/27083123936.pdf
    • http://mjsolankifoundation.com/fck/imagesfile/46233107525.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/ta30d7jkvibqsjf0nct1ivf0b4/toranoxuvarafa.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/40a173a85be0e65e2e58dae13b6afd6b/94120516627.pdf
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/2hodcbtqnnjvr8ceahpqurahcj/53987460102.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3487a43de---xotasivuwuponizozu.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd8cfe2594---zobukuril.pdf
    • http://nowyhotelik.pl/userfiles/file/54939153775.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/566cfff764310c63e4fa5d279d1a8e51/79592326207.pdf
    • http://zonazero.es/userfiles/file/26724123864.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e560a2ac9---38950461753.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160fbf2a44dcaf---muzifijemel.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=can%27t+turn+off+safesearch+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_off00012edd.bin
d2ab7f6908e21b609c9289d0fb7a494e28500ba5c3f0d9b4901d90a6f96faef4
pdf-font-stream PDF embedded font (sfnt) at offset 0x12EDD 19732 bytes
font_01_sfnt_off000160fc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x160FC 16792 bytes
font_02_sfnt_off00017913.bin
017482422b02f628219bff695fb2f8b5dfa67a4ae3a4d407b81ac412307379d1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17913 10628 bytes