Malicious PDF — malware analysis report

Static analysis result for SHA-256 4608c3939700f3ec…

MALICIOUS

PDF

84.3 KB Created: 2021-06-26 04:19:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 24b688a7a50e856cbef753c3aab3df41 SHA-1: 3fde9311eed77915fa0c5ce65f3d90a52d6a8f21 SHA-256: 4608c3939700f3ec24e9dd63a982e2b2172761af27f9e91f38ce9c6aaf8f6a1b
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, likely intended to host malicious content or phishing pages. The ClamAV detection and ML classifier strongly indicate malicious intent, classifying it as Pdf.Phishing.Trojan. The document's structure and URL patterns suggest it's part of a campaign to lure users to malicious sites, potentially for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c78295f3e40---katodejukifoju.pdf In PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/7c292eb68682ab3e433b197559495583/79485533347.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/usbsmosgbh4k03huc9t4loe15r/78925464503.pdfIn PDF document text
    • https://acrgroup.nl/userfiles/file/losamalutulazimevitok.pdfIn PDF document text
    • http://heyumpnd.com/userfiles/file///belunewewivazidowokiwot.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788f88822ed---96107218074.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160780f2611a67---ganupejebegirolekiz.pdfIn PDF document text
    • http://poorclarescork.ie/images/wufojonevorovegovomapole.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d4ad9f2e4---40695362188.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/1unr9v6obut9og5b0m15moqlp3/vekoxideburaxavedopadel.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c53f72e7145---zukin.pdfIn PDF document text
    • http://www.zaluziemalina.cz/userfiles/file/29429728000.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1fb05d064---mudoxoxuranivubuf.pdfIn PDF document text
    • http://cheers-gifts.com/userfiles/7966055343.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/a87cab8e3b8ee9634cc1f001f11524fb/66630048254.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608724b5a805e---1969226447.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160a872d310cbc---nogisuxesibupugenemitawir.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/9fca511b364395dd816aa10902e8e862/80177060659.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/fenijozevipenugiwizigibar.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c5ecbb6fef8---vadifiletoba.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c3cf786150f---69672741108.pdfIn PDF document text
    • http://stl-hk.net/userfiles/kuxiwotelezavujed.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/keludofoxumamixewasugaf.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/ba57f2cbfc4ef33fe792407fd97dbec3/94189520251.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/kizutufizetipuxav.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aaf8dd204d---31041929830.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=movement+of+unicellular+organismsPDF 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_off0000e564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE564 10840 bytes
SHA-256: 9d476376b6c51804d1cf4f94d516511af4f8382723faed54ad0fbd0a911c156d
font_01_sfnt_off0000fe6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE6E 17640 bytes
SHA-256: 1ec8b81e3345739dbdba63ce5733ccd207afd518dbc95593f3940f360db6e876
font_02_sfnt_off00012be9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1