Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1063628c1b01ed0…

MALICIOUS

PDF

93.9 KB Created: 2021-07-03 01:34:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4456ca453d8af80c312af62f935e558a SHA-1: bcf4204e08ff8328236c36379a8b0d76a1b517e3 SHA-256: a1063628c1b01ed0c23666c2f2b0987f38f3aa5bc35abee4e49e1745508c6ea0
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised websites and disposable hosting, suggesting it's used for phishing or distributing further malware. The presence of external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

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://krisoc.ru/uplcv?utm_term=interstate+removal+services
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608173835af0a---doguwogafaxoretovupewusu.pdf
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608c5a8885d5b---morusabozozebeve.pdf
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a84d8590bad---88144193562.pdf
    • http://cesurmakina.com/userfiles/file/6333408044.pdf
    • http://metallpress.ru/files/kujafu.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160736b259b496---95878155126.pdf
    • http://cristal-in.fr/userfiles/file/pomuvowewuxesasume.pdf
    • https://ruiguoex.com/upfile/files/2021/06/05/80885556147.pdf
    • http://rentbucharest.net/images/userfiles/fekojizapotiwapavi.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/526f199128bfe2e91583399be979b8cc/fakiratidefunaju.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/rs0svmumkm6gsa5u2qpjb9j6k0/68600760055.pdf
    • https://clubslotalmatriche.com/calcas/file/51009753190.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/1p92vo5tpf30lr2erfrm7o21td/jaxawakiw.pdf
    • http://iphysiology.ru/upload/59642105773.pdf
    • https://alexandrapanayotou.com/web/images/static/file/semifojolez.pdf
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160d96f4a19b57---xizejonuduxudinev.pdf
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/a924c0af0892ffbe036033a00d0ba5d3/lupabugiba.pdf
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806a50cc011---33801333320.pdf
    • http://cottoneauto.it/userfiles/files/lamaba.pdf
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8ee189c618---25651604052.pdf
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/b3616737d2791e4ea75aa7b422525301/wugamagapawugunawir.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/c91a0eb0349d7724f01561854494c8b5/44006396852.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/86b2f6e2b498a2fedbb9967575a52c39/79497278078.pdf
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/323da60a75fec16b5878144d1b90917d/66216726427.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f75a.bin
125eb871611eacf4abb8f8b1ee1cde29d9cf62005199cd875a8f1f4eebdac6d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF75A 17412 bytes
font_01_sfnt_off000124bb.bin
8214b55e030c3cb37d727e4c02e4f9fe3cb7b8fc3885df20e34cb8ea79a6e3ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x124BB 16172 bytes
font_02_sfnt_off00013a55.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A55 16792 bytes
font_03_sfnt_off0001526c.bin
a0e2dd636bbfa82e22fa9cf3b8a781eb6f93050a395cd47943fbc19d27322464
pdf-font-stream PDF embedded font (sfnt) at offset 0x1526C 10408 bytes