Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a597d6e4f67887f…

MALICIOUS

PDF

165.0 KB Created: 2021-07-06 22:24:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5193bcf24f532e893fc84ce40bbc2be3 SHA-1: 6e6363b8eefff232032fe56b3f1fad8b1dce15f8 SHA-256: 6a597d6e4f67887fd4e47d23cebacbd2c0952830ecb2cf36764a783fa7ca4047
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it's designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the link farm nature of the document is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9903

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=intracranial+hypertension+causes
    • https://triptoboloyfoundation.org/editorsfiles/files/63025690121.pdf
    • http://aaaexpressac.com/userfiles/file/jumeb.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160841321c836b---1600498132.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1607faebf70778---58854201204.pdf
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/frkim8o6hedhmi6cg6mg7chfbi/99621279251.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bad2c5a0084---3108174241.pdf
    • http://candientushinko.com/images/file/45975624480.pdf
    • https://alshamiltrading.com/alshamilfiles/file/kinokusapalujagariw.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f533b1ade1---50913442895.pdf
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607698d596e7c---12965516972.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a6eb364305c---58783371616.pdf
    • http://casier-a-bouteilles.fr/file/wakekarelogebon.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/b4fae8e89eeadda0567b6184f37b238d/84984249867.pdf
    • http://mikailang.net/userfiles/file/20210516163745_627696444.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c1c91e9b884---pekokefimawuzixusu.pdf
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092718a3b369---dovowusezonowaxaka.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/tmp/89257932761.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0afbb9cf8a---64902875162.pdf
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0fa915822---48819991790.pdf
    • http://bidmitt.com/img/files/file/76091476780.pdf
    • https://pet-fashion.ro/mm/file/54030399017.pdf
    • https://marbellamohali.com/wp-content/plugins/super-forms/uploads/php/files/70fc10b16c12c0ef51690000eccd4b29/41174769455.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609760ccf14b4---xuvefunazujikunux.pdf
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ff9924b56---53215391192.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_off000225da.bin
83c1a487276a1125b1d397dd264153b943eb6f55dcae78ca74525d042e350785
pdf-font-stream PDF embedded font (sfnt) at offset 0x225DA 18316 bytes
font_01_sfnt_off00025626.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x25626 16792 bytes
font_02_sfnt_off00026e3d.bin
05df2c341fa35c2503ae3a3125d6500d5f6331b2d9d01ca9a010d95d416fd47c
pdf-font-stream PDF embedded font (sfnt) at offset 0x26E3D 10636 bytes