Malicious PDF — malware analysis report

Static analysis result for SHA-256 b66bd08f99ca9572…

MALICIOUS

PDF

104.4 KB Created: 2021-08-17 02:27:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c20d6952bd893772cae278947a45143d SHA-1: ab6495ddebb3d0ca586f0d0d145d2761e63cb084 SHA-256: b66bd08f99ca957216fd5cbf0d8bee616ebbeb908a83170919dee632a52f4097
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links to external websites, many hosted on compromised CMS uploads, suggesting a link farm designed to redirect users to malicious content. The PDF structure itself does not contain readable text, but the presence of these links and the heuristic firings strongly suggest a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9885

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 http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c44aa73a5f6---66518727821.pdf In PDF document text
    • https://alienaquatics.com/home/gb/public_html/ckfinder/userfiles/files/mapikazilojusegovemeb.pdfIn PDF document text
    • https://fwullong.com/upfiles/editor/files/wipole.pdfIn PDF document text
    • https://machinex-machines.com/UserFiles/File/25825139811.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/16102f658f254e---midoxidirofopex.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/d7tcfacma22p3slthq5ljkcb25/35397280890.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/lodelejojiwi.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/punokowesaxazekir.pdfIn PDF document text
    • http://vitacanes.com/uploads/files/10838392790.pdfIn PDF document text
    • https://cahayamimpi1.com/contents//files/23319364461.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e5f8abd93b---57484554118.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/81700b60a670ba75f2378fc4f8a30d29/22963799888.pdfIn PDF document text
    • https://iveducentar.com/uploads/assets/file/58256407646.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f4be05614a---45820442713.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/disalobawoposubi.pdfIn PDF document text
    • http://cosyromania.com/media/file/47079281883.pdfIn PDF document text
    • http://maginsaatmetal.com/resimlerfiles/50191070940.pdfIn PDF document text
    • http://spy-military-labs.com/userfiles/file/35673278506.pdfIn PDF document text
    • http://hz-karavany.cz/ckfinder/userfiles/files/38131773820.pdfIn PDF document text
    • http://mbcasc.net/imgs/file/luzoxakavobuwametibuvu.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/fanepaganoxa.pdfIn PDF document text
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/30292451412.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609de0672cf80---14914802446.pdfIn PDF document text
    • http://bet-balance.com/userfiles/file/46480942642.pdfIn PDF document text
    • https://garyjetcenter.com/wp-content/plugins/super-forms/uploads/php/files/e9a5f3c044c7f54e3a575f3c277ee0bf/40698560731.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=engineering+mechanics+statics+12th+edition+solution+manual+pdf+chapter+6PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off000109ea.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x109EA 22848 bytes
SHA-256: e56fdff910c294468d8bd505d1bdc5d98d1e69e1d4c4d4d754c8e37783ca2517
font_01_sfnt_off0001321d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1321D 17544 bytes
SHA-256: 83bd60ae29237ac6dd5d6ea4ae7457d278391073a0bc4c48afd86415d47d0b07
font_02_sfnt_off00015fbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15FBE 11488 bytes
SHA-256: d180a1ed100979f246f97bf9b3fe884bf6d82d8ef1b853c7edb05ca8bd9997e0
font_03_sfnt_off00017a9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17A9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1