Malicious PDF — malware analysis report

Static analysis result for SHA-256 861e65b5eeaa7c03…

MALICIOUS

PDF

78.8 KB Created: 2021-07-16 05:03:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b811d5abb44fb0460cc5c2be43c5034d SHA-1: 770a95148545084a353a7ab29fb952aa5f3bf15c SHA-256: 861e65b5eeaa7c034c7fa1083b9556f991677eac30a91896f5ec3686b8e333ad
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically indicating a phishing or trojan threat. Heuristics reveal it functions as a link farm, directing users to multiple compromised or unknown domains, many of which host PDF files. The presence of external URIs and link farms suggests an attempt to redirect users to malicious content, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://amthanhanhsangchinhhang.vn/upload/files/wunoju.pdf In PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbffc74e20---pugilogedixakesofitamo.pdfIn PDF document text
    • http://cherishedmomentphotos.com/clients/8/84/84fe84b553acfcd191e166b7401b6f02/File/xuzotajowo.pdfIn PDF document text
    • http://canvangdientu.com/images/file/8269700952.pdfIn PDF document text
    • http://tamlaproject.com/userData/board/file/batavutog.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160858895acf9f---23777865709.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/puworeze.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16099c78aec5fe---bizovajozenofupawifur.pdfIn PDF document text
    • http://gospelinamerica.com/clients/874377/File/juloneterimumokozib.pdfIn PDF document text
    • https://maggies-handmade.com/UserFiles/files/5817481576.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606df30aef253---kiwapivowavikop.pdfIn PDF document text
    • https://betentour.com/sites/default/files/file/63882157444.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160df5af5742c8---sakalejedefegufibe.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c2aee737323---60386285479.pdfIn PDF document text
    • http://marta-galan.com/files/varios/file/9731120560.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/7e2880f506ee22388ed04d24d3a14918/tunos.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609bd9080e0f2---wopukuvaro.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/107f64f732174d81dfe55499b5c8015c/gudolimovusuzibinadu.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c43edb91b51---jufixu.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/ffe1221540d2491eb8054093031a79be/nofaro.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081eb9529291---59783390622.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/juvawewejirubejabiluj.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/jugudolozasudulafizutekab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=malaysia+derivatives+exchangePDF 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_off0000d144.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD144 10804 bytes
SHA-256: d5432442f8cca2611f7777928f02a8772541ec7812771cf358427625f5db8cca
font_01_sfnt_off0000e9f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9F0 16824 bytes
SHA-256: 0a73371343dd88d2a25eae2fa3909e5686f0722dc3c0c9818aa07337edfff691
font_02_sfnt_off000115e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1