Malicious PDF — malware analysis report

Static analysis result for SHA-256 b509d9848c49d279…

MALICIOUS

PDF

82.9 KB Created: 2021-09-22 11:44:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f3ad87cbbb62e503b98d3ba74bea8ed3 SHA-1: 2e6dc04c88c8bd370b14a86a090acb374566471b SHA-256: b509d9848c49d2799c47c56cf72d26cf557a35839d79d1c1de76021dbe6c4630
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm for malicious purposes. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded JavaScript is likely used to facilitate redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://teen.plovdivweek.com/js/ckfinder/userfiles/files/56457110349.pdf
    • https://krantiservice.com/ckfinder/userfiles/files/jikudezodi.pdf
    • https://wfbulgaria.com/uploads/wysiwyg/files/xewuga.pdf
    • https://mr-alian.com/upload/ckfinder/files/gobegodovebugixamedusab.pdf
    • https://kamhosting.nl/ckfinder/userfiles/files/55081087669.pdf
    • http://oralrem.kz/ckfinder/userfiles/files/26550798478.pdf
    • https://kalitelivideoizle.com/resimler/files/mosam.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139622ce3d5d---80328263931.pdf
    • http://americandeliorder.com/uploads/files/47935996413.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613df1f47eacc---vutanotovesemudubig.pdf
    • http://mirsistem.com/depo/sayfaresim/file/18341496237.pdf
    • https://grdr.org/paidel/ckfinder/userfiles/files/xojejolulikozuxunijajelo.pdf
    • https://lockerova.eu/admin/upload/documents/9849986578.pdf
    • http://dija.lv/public/userfiles/file/59376885223.pdf
    • http://invismortgagebroker.com/images/file/72728582538.pdf
    • http://fortwashington.abwingsmd.com/uploads/files/65017785661.pdf
    • http://wmasgroup.com/userfiles/file/zixut.pdf
    • https://estoniapools.com/contents/files/72732536310.pdf
    • https://ev-owners.jp/userfiles/files/sinikofipil.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec9809b886---jufizepi.pdf
    • https://ausztriasi.spawellness.hu/upload/hirlevel/files/zafulejoxi.pdf
    • http://gorisum.net/fckeditor/upload_file/file/jexiluvifamiga.pdf
    • https://www.benkorner.nl/admin/library/ckfinder/userfiles/files/4267004108.pdf
    • https://trexanh.net/upload/files/wogifaj.pdf
    • http://sterenstein.ru/userfiles/file/lutaxejujivifunuzugigajo.pdf
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613035f145b59---90719849695.pdf
    • http://kovospm.cz/fotky/file/xinixazovifebuzevemuruxur.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=backyard+baseball+unblocked
    • 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_off0000deca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDECA 16792 bytes
font_01_sfnt_off0000f6dc.bin
d6d9f75491956a5fffdd6d9b90210266ff4a39c818fb8ca5a361dacae62c2282
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DC 17992 bytes
font_02_sfnt_off0001259f.bin
c9d3121c6c20925461ca3ae2755c824b406cbb8fd13e9a073d0ebc9b3f6cac76
pdf-font-stream PDF embedded font (sfnt) at offset 0x1259F 10672 bytes