Malicious PDF — malware analysis report

Static analysis result for SHA-256 5385dba543eca5c6…

MALICIOUS

PDF

82.4 KB Created: 2021-08-18 15:38:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b9525e695e987b5f2c77fdb5e59aec78 SHA-1: 51bc14d1487bdb8f19bb1028ff806002c7730743 SHA-256: 5385dba543eca5c624754377c804e786a1bf351cdedeeb18ecf3c500551275ee
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document is a link farm, with many URLs pointing to compromised WordPress upload directories, suggesting an attempt to distribute further malware or phish users. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f173eb82ad---zozepibobizunek.pdf In PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/96133373319.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/43e5934aa69beb3cd5009fd073bd405e/57156412530.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/fazizos.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/42cdf7b9cdeb7db4862c867c0c0ced1a/romenokarejodexugog.pdfIn PDF document text
    • http://ofipapel.org//ckfinder/userfiles/files/67067730162.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/63345281737.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/xatuzugukazaru.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160b4be0f0aea5---47434653724.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/q4uvqcj87ngj9bigftb30be7aj/kapagexotekadatak.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160800bec4a687---6906614962.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/49005f52fabc9a71ee1a3e206e74f017/43519511361.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/12932965742.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/37912684657.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079cf8062730---pomix.pdfIn PDF document text
    • http://ritadas.in/userfiles/file/69610973328.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a90f3b1fe25---vimeto.pdfIn PDF document text
    • http://nowator-zpu.pl/userfiles/file/zakopuba.pdfIn PDF document text
    • https://autoprofi.ua/userfiles/file/darupadegufujunaderufit.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/77nbkmgg9b3ujq7ojvgto33mug/40350010892.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a940e2068f6---zegitomesul.pdfIn PDF document text
    • http://northphoenixmustangs66.com/clients/4/4b/4b49b54eec06ebba3741256e9f3e6f2b/File/redeko.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/zukorolo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=how+to+combine+multiple+word+documents+into+one+pdf+macPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDDE 16548 bytes
SHA-256: d08113aff6587aa74902ad11c26e9a8838ae2d62d2a1040e5b151e1b86f77643
font_01_sfnt_off000108c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120DD 11100 bytes
SHA-256: b588597612fe4c479d89afcf78927a12a035a95b6b3c2578b45e81dbc095acb6