Malicious PDF — malware analysis report

Static analysis result for SHA-256 9255aa3813e336b7…

MALICIOUS

PDF

80.5 KB Created: 2021-09-02 15:04:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0c0702366a2a249389fc833e38ca1f45 SHA-1: 255a50733f3dd95883b1b395d9a73080004f38f2 SHA-256: 9255aa3813e336b74cce48b8c96e283c3251f1359dd7972bfdd9b3cdf983a4f7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics as a link farm, with many distinct hosts and URLs pointing to compromised CMS uploads. The ML classifier and ClamAV also strongly indicated maliciousness. The document body was unreadable, but the presence of numerous external links suggests an attempt to redirect users to potentially malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/g44egdok2013v3os20ppim5o0q/ruliwobumedegog.pdf
    • http://koreaseals.com/ckfinder/userfiles/files/gafebakekimazewus.pdf
    • https://groupburuemas1.com/contents//files/bosuxulenisudebesomili.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/qkbvo2n9tf53deas5ir9mfpvjm/27714039469.pdf
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160fc479d8e3ca---13808642191.pdf
    • https://yoimart.com/upload/file/20210825063405.pdf
    • http://finemetal-cn.com/upload/files/sesulovu.pdf
    • http://rdasesores.gestconcursal.com/editor/ckfinder/userfiles/files/70270372943.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/iffc9lccge2b2ij22qroagq7k6/nekudital.pdf
    • https://evergreencans.com/userfiles/file/tubalijatixujafunedesu.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/f603becfb5b390e58460f25c0e0f2c0d/juvipetuk.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/ed7fad06ba1c8d7b5e778d5687dcacc4/75298368304.pdf
    • http://tsmsaldature.it/userfiles/files/52604650584.pdf
    • https://etest.vn/app/webroot/uploads/files/17626129350.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608de584ac200---72506604428.pdf
    • https://www.herewardcarpets.co.uk/wp-content/plugins/super-forms/uploads/php/files/gcpacurcsq017q61hskshhoil6/90715441673.pdf
    • http://domuran.pl/files/file/70523855089.pdf
    • http://vce34.ru/attachments/file/muwuvedetak.pdf
    • https://szaniterplaza.hu/ckfinder/userfiles/files/fexenot.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160bc2e9d57379---setetibunukaxog.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161204782120fc---buzebe.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/7bf820864076af509edc520368185f1f/9037747075.pdf
    • http://parquessolaresdenavarra.com/userfiles/files/39948228710.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/161131d7a3d891---kokavunavezaroxefes.pdf
    • http://barcabianca.eu/upload/file/punubenade.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=beginning+%26+intermediate+algebra+5th+edition+pdf
    • 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_off0000db8e.bin
f6a782dd78746179251c61e483ec59a140cbd72df2980eec1ea135075cfffc3c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB8E 9636 bytes
font_01_sfnt_off0000f077.bin
7fd5a84393c646e2b2c604db3453cde5440356adba55eab59a78d4e276a780ae
pdf-font-stream PDF embedded font (sfnt) at offset 0xF077 17088 bytes
font_02_sfnt_off00011ca3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA3 16792 bytes