Malicious PDF — malware analysis report

Static analysis result for SHA-256 d006c5540e1fb78a…

MALICIOUS

PDF

85.0 KB Created: 2021-07-03 07:55:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8a22311e90e04de57baad6eb9465f988 SHA-1: 962cf25f392e425b02e6b584e8e73f9109388b50 SHA-256: d006c5540e1fb78a73c44ceb0ad71d95f7ee4fa387e2925d3dcf15c950bcb749
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous embedded URLs that point to compromised WordPress sites and other disposable hosting. These links likely serve as lures for phishing attacks or to distribute further malware. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but containing structural elements indicative of its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://queure.ru/uplcv?utm_term=subset+of+integers
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/lp36h15atg4nrcichqfubq11d7/75177945761.pdf
    • http://netinflux.net/userfiles/file/7719501033.pdf
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/ab50c367f6c084a71fd82f9093dead2c/bekufuna.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/000eaece66eee9e548d49f77211c09a4/zikeroweke.pdf
    • http://superfishinglewood.com/uploads/files/zirotupezoza.pdf
    • https://hometeamcorp.com/images/usr/72894494864.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/292a10473e4163c6ccf5c85709246a81/tateporateboberudiwelere.pdf
    • http://expertsystemgroup.com/file_media/file_image/file/41849468609.pdf
    • http://paroissedementon.fr/upload/files/14685929823.pdf
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16086f0f386589---riraza.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/jl3o6pnnsv1ceps2iicfmhd9v7/riziwinutisizo.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16079db8d2eb5d---25537594995.pdf
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/c5lj5399hgnm9bl6e8r58mpvq4/tokivemefukugavab.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16099fb76d29d8---galabil.pdf
    • http://vodnik48.ru/content/file/23111623001.pdf
    • http://czdashan.cn/uploadfile/file/2021042921541573499.pdf
    • http://www.mezmat.ru/ckfinder/userfiles/files/61584531328.pdf
    • http://yangpupark.com/uploadfile/files/vamogenifaxuwarigir.pdf
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/91e900bd498f278728b2902f52507e03/87195663260.pdf
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e0b6260aa---zakosepolu.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16090bc924caff---xudewogu.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083b52ebd459---toxanuzipik.pdf
    • https://bonafideonline.com.ar/wp-content/plugins/super-forms/uploads/php/files/9181d963ccbbc814e66e71034fa2ef48/93634498768.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_off0000e1f2.bin
8029de223bd5a26674ba45dcd964b378666b07509c04a4684fc2c12ec10921ac
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F2 10496 bytes
font_01_sfnt_off0000f9f4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F4 16792 bytes
font_02_sfnt_off00011206.bin
eac168de4061a25fd88c75a9b979e1137202b2cb3d4cacdb0e4553f5299c145f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11206 19196 bytes