Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e101cc09308dc5c…

MALICIOUS

PDF

86.3 KB Created: 2021-07-09 10:41:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e0b8c40224189797794e87ded68ec187 SHA-1: e13fa98d6901adc2e566b5dae587383bbe69f1d9 SHA-256: 4e101cc09308dc5c9b8bfadd3e58eb913aa479f5fb777fb3c83fffbe331ece44
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the true destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/eb89451172c1d562f35684e654dc86e2/54878606010.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cdf0728b2cb---jadolexivufosupifovaje.pdf
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/24611976599.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/aiiubf03totd7a0a109df0jfm7/lebudalesi.pdf
    • http://alexlunacoach.com/img/editor/file/gabuwabu.pdf
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c889e810f9e---tidogimujamo.pdf
    • https://securitegenerale.tn/userfiles/file/visuxujikojixikofudiro.pdf
    • https://airshow-bg.com/file/dijodizipojobino.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160ae96d1132cf---kumiw.pdf
    • http://aedelsur.com/contenido/files/35359954593.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/2ca495e7daff426cc0b10bc492b00555/6721167205.pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/e8d216c998263cb12e19aa50193c6ac8/51237647944.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c6388286281---jakugezirotufad.pdf
    • http://fouladsazanco.com/Upload/file/nulanojan.pdf
    • http://shinex-auto.com/userfiles/file/28914994780.pdf
    • http://moestuinwebshop.nl/userfiles/file/voxape.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/0jmusa7ml48a6nma2tkreoeofo/2471212979.pdf
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/d92b2bb1ed75728818ca7f118c69f3e0/nufizeberixobipu.pdf
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/nd0d3ulcfqqrafpmqaoevtbje6/wexawabegujubotoxu.pdf
    • https://atraba-holding.com/userfiles/file/kuxujozajowoguni.pdf
    • http://syuncyoku.jp/upload/file/58736484540.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f61f568b82---dimolokapupebezeratar.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b28270d278---29459782190.pdf
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/bejobi.pdf
    • https://performanceltg.com/wp-content/plugins/super-forms/uploads/php/files/bdf4c29f349c6da04ce8873f2a16bd52/21166686519.pdf
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/33098936916.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=word+search+puzzles+for+kids+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_off0000efed.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFED 16792 bytes
font_01_sfnt_off000107ff.bin
ad6c12b29c3c1f754737daf319a19b126ef10a9793c8e52b7bf10d8e53388793
pdf-font-stream PDF embedded font (sfnt) at offset 0x107FF 16484 bytes
font_02_sfnt_off000132df.bin
4b883c16c0e3416e138d716271dedecc26e3ac06ecb53613287a783bf4cbed05
pdf-font-stream PDF embedded font (sfnt) at offset 0x132DF 10760 bytes