Malicious PDF — malware analysis report

Static analysis result for SHA-256 78b781f0d34c52d3…

MALICIOUS

PDF

87.2 KB Created: 2021-07-06 13:02:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e2af54cbb90d621c222c6ea36aa02a3b SHA-1: 78ebf471acd0ed3e3d7fcf1c977cffc41844595b SHA-256: 78b781f0d34c52d3087ba03057089ca1e6b86468b4f3a72c5e8ade501615ce3c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF sample was flagged by multiple heuristics and ClamAV as malicious, indicating a phishing or trojan distribution attempt. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm or redirection mechanism. The ML classifier output of 0.995247 further supports its malicious nature. No scripts were extracted, but the presence of external links and the overall heuristic profile strongly suggest it's used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://infrive.ru/uplcv?utm_term=what+are+the+job+interview+questions+and+answers
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b8186140e6b---lebugi.pdf
    • http://arenda-v-novosibirske.ru/ckfinder/userfiles/files/vafura.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609da6bbc401c---lijojoruzotane.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/20e81a26ccb401f1f9039374ace0835c/lutezuzonezudivunufisar.pdf
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/911f1e47ca12329d39914855806c59be/67508734010.pdf
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d57866f9d1---gatibudubupuritopomi.pdf
    • http://mtcongnghiepxanh.com/upload/fckimagesfile/89764631522.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/6f288578218f98e38e61914bd7e3266d/66568454887.pdf
    • https://ajwatravel.com/wheelmarine/userfiles/file/80893970613.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607170d60a931---27365773197.pdf
    • https://pristineleather.com/userfiles/file/53079083511.pdf
    • http://cariboohose.com/userfiles/file/21036104216.pdf
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/7da6e12a9f016abfb19ed4b6e2a55226/vimofevesebojojeleze.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/56875134880.pdf
    • https://cowichanseniors.ca/userfiles/file/xuvibawet.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/0cae4d6ac162d7c1f2bd8f966707b700/52551849065.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160701ca475859---42135969239.pdf
    • https://pfhotel.gr/ckfinder/userfiles/files/fawilaval.pdf
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/330hc9s5kokbebgl203ih8ebe7/wobabadejemagurug.pdf
    • http://chixue.com/uploadfile/file/20210626151405.pdf
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/7e24797e8f5b7c80ffd227a4df704a49/88773172289.pdf
    • http://dailitara.lt/bites/uploads/file/musexuw.pdf
    • https://jackyrouxmethode.com/userfiles/file/31100388679.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_off0000f24a.bin
ed3a66d6a338d55a9926a8b84a7eef24c1d6f14c60f1019346e9d4dbd1351823
pdf-font-stream PDF embedded font (sfnt) at offset 0xF24A 16924 bytes
font_01_sfnt_off00011e32.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E32 16792 bytes
font_02_sfnt_off00013649.bin
f5120d3d432b808b036e38b469bdaf125efd8cd8baa56b9c3e861458ec59a857
pdf-font-stream PDF embedded font (sfnt) at offset 0x13649 10960 bytes