Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd06bf7d1c2c1b9a…

MALICIOUS

PDF

77.5 KB Created: 2021-06-29 14:26:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c91153245edd47601296b9f3ec07e35 SHA-1: 333e141aa633f0c3248cb606b7398719d84dd9ba SHA-256: cd06bf7d1c2c1b9a47761ac6176e5128a57b92dc20f8308cbf2e1e0f6f71aef3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it functions as a link farm. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's likely a lure to phishing or malware distribution sites. No scripts were extracted, but the overall structure and URL patterns strongly suggest a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://infrive.ru/uplcv?utm_term=4.5+tbsp+to+cups
    • https://systematix.pl/userfiles/file/vebeluzegubaguboje.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/a953676b0ebea8e5fc2850b895f9ce53/90625501874.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/dfd0938992a5732a471fe746cb70f777/18037895926.pdf
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/1a55784ec96a7774c516c2f73f3ff9e4/kiraraku.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d92a772f04.pdf
    • http://syuncyoku.jp/upload/file/58736484540.pdf
    • http://amdind.com/userfiles/file/fegozilifupove.pdf
    • http://aarogyamedico.com/userfiles/file/15721388591.pdf
    • http://flygarfield.net/userfiles/file/ladufo.pdf
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/22b9e22254403853e6572929ef762890/32675189896.pdf
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/281996721ba079562c642587381fbd8c/96516160322.pdf
    • http://mega.kz/media/upload/files/44771264422.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9589be7e30---venedavoxu.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/3fbf9448796384167d4105142c4f6e6c/fixasisubalusezufamatages.pdf
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b616a59737---67793362045.pdf
    • http://chekeeh.ir/basefile/chekeehir/files/26439282561.pdf
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/46070bf9a7469ab4a64e5f5d02d87369/8079255574.pdf
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/qaknmnldjojva0sob3jh3jmea4/dolozodovujekexaka.pdf
    • http://mp-hd.de/data/aktualnosci_imgs/file/gixapufepebuzip.pdf
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/3be305b9c2a6855fc390624a6d19a292/vozorofipotewituwabex.pdf
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/ed8q36nupqbqlh1kca1cvit4r1/ligipobuzig.pdf
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/ad9fedefcef9e542b0b31f32ee166a76/32352632148.pdf
    • https://qualitymattressfactory.com/admin/userfiles/file/zamemiti.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_off0000cbc4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC4 16792 bytes
font_01_sfnt_off0000e3d6.bin
7e88c6c4990c9c9671abcb18ab80cdef889c43102bd873fc716fe2b43f1c748c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D6 17684 bytes
font_02_sfnt_off000110ef.bin
8628fb50cee4796f1e800e704558088c21e6a7b1a62cb6ac33e9c9ce7d98544a
pdf-font-stream PDF embedded font (sfnt) at offset 0x110EF 10152 bytes