Malicious PDF — malware analysis report

Static analysis result for SHA-256 3bb1b90f28cb5caf…

MALICIOUS

PDF

93.7 KB Created: 2021-06-27 00:30:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 18c21cfe1315122a2e41e3285cee64a1 SHA-1: d848f374a4d06bdcada4e4c17dd65709c9824c46 SHA-256: 3bb1b90f28cb5caf08bd5e7c93ab8bfb737ae725b10e70d96be8df20a8e77781
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics suggest this PDF is part of a phishing or malware distribution campaign, likely delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608f641ca4931---xupapivesaratujagemonaw.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160913dcd4d469---kolejowafida.pdf
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/varalowaxu.pdf
    • http://fw-simple.com/uploads/files/dajovune.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c85b8be164---80116174097.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090d291c61e1---mufifavomojivafukofe.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/85hshsl3ktqhit2i3mjuh3eeoq/29184576860.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce0dda70d9---13050624037.pdf
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/4b5975d1cfb048b1bf2dc01c96b5665c/besov.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b31248e8b6d---69851954391.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/c9065ee6ded92ab90a4ba24e3c02b8c7/21828479354.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea6fe21630---38070316228.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f7c4113585---kefiwuzogabutobut.pdf
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a9a2dfcd6---jabezikowidatosuvugesi.pdf
    • http://nguyenthaotech.com/upload/files/bijonobufojalafaxexo.pdf
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/tn8pl9tnlj4v0q6gg4d357ies2/wuturem.pdf
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/50gs3c2i9u76k93vpmjtp059j0/nuguj.pdf
    • https://et-auditing.com/userfiles/files/zovimazididivemo.pdf
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/c27cimfg8cn9os0ankhv0em2fu/47304730144.pdf
    • http://nedirajtebosnu.net/userfiles/file/lupobu.pdf
    • http://kahounova.cz/userfiles/file/murivigixotuwi.pdf
    • http://mabo-meccanica.eu/userfiles/files/kebetasenefiba.pdf
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/tbarq5ts07v7bs8i31ip1s8ak1/titasalezun.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/vgsput0v5ss6jgvn8t2vm3oiik/96009246498.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=vocables+in+music
    • 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_off00010896.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10896 16792 bytes
font_01_sfnt_off000120ad.bin
df8a33916c647c3cc38a20c6ad8b0c898c4d824fbd197debac0197505c3abf9c
pdf-font-stream PDF embedded font (sfnt) at offset 0x120AD 10404 bytes
font_02_sfnt_off0001382b.bin
4d67e1a8a3b01d8851efb02758492a36cffe10d5b24a182d494017bcd8171006
pdf-font-stream PDF embedded font (sfnt) at offset 0x1382B 18228 bytes