Malicious PDF — malware analysis report

Static analysis result for SHA-256 f636b9538ae0b62f…

MALICIOUS

PDF

91.1 KB Created: 2021-06-27 02:49:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7019b3d3e3a801ba21f52134e64e765d SHA-1: 9d459f368a5b017854415607e9f80a6f2da71079 SHA-256: f636b9538ae0b62fe70fce28445fa4d6ee4bfb755a50fa16053df1d96956a68a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to various compromised websites and disposable hosting domains, likely to facilitate the download of a second-stage payload. The presence of invoice-related language in the document body further supports a phishing lure attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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 http://cdhsalumni.com/clients/28864/File/96706497548.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca0f0792d91---37785242505.pdf
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/2d3s223nbptur6qciqnku2i4mc/66532660235.pdf
    • http://lookkorea.net/userfiles/file/17590192200.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086f80122732---40331227113.pdf
    • https://baongochoa.com/upload/file/58990779324.pdf
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e691b3f2a---74556494529.pdf
    • https://syteq-pro.com/userfiles/file/42207002632.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160b6f257cbfd7---xuketuvakiboluko.pdf
    • http://xn--clinicaquirogavilario-vbc.com/wp-content/plugins/super-forms/uploads/php/files/35s4sujqa5t05irsbu4lm8smm3/filowotimelumate.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607805a2e243a---kebabobeb.pdf
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/ht25s0stopap1t8jstlhcepj7d/gobafufubudix.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/d18384b4fc3e5e56c775ac28bfb3db49/felox.pdf
    • http://aelma.com/sites/default/userfiles/file/girilepodez.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609aee82cebf0---fizosawujidi.pdf
    • https://zivotzaokny.eu/res/file/gojasimo.pdf
    • https://ajitcoatings.com/uploads/bimananategin.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b3c187000b9---69123756342.pdf
    • http://warraichmeats.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077514e3f501---gebid.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608797bf0ca9f---pexepedokelaxeniwepozax.pdf
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/cchh2aljn48crosqc5pguk4ru4/kaxerufiwad.pdf
    • https://actorconseil.com/files/file/44832983317.pdf
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/frrp2cigo5e4hupsi34vtbotvd/padatozavunazujul.pdf
    • http://aodaibooking.com/FileData/ckfinder/files/20210623_C63B9DAC5A2B1ED8.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=income+tax+commentary+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_off0001016e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1016E 16792 bytes
font_01_sfnt_off00011985.bin
5916b6b5011592c8b8f63f355be87ac431967bff3c3e176dd2f32ca3df03b809
pdf-font-stream PDF embedded font (sfnt) at offset 0x11985 10644 bytes
font_02_sfnt_off000131e8.bin
04676e40a1de1d70915ec4b84315849bda06901c07ee328086f4dc599ba1ac48
pdf-font-stream PDF embedded font (sfnt) at offset 0x131E8 17484 bytes