Malicious PDF — malware analysis report

Static analysis result for SHA-256 681d03e49cfe095a…

MALICIOUS

PDF

88.2 KB Created: 2021-07-12 17:15:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 4db346a188c1bd86bfd0588301f6e170 SHA-1: b9e70bf22796938a46b7bde0c75258608ce4adae SHA-256: 681d03e49cfe095a654e63ccc5adb1ecf382a92c8f08b16091ee04bc486646f3
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a phishing or malware distribution scheme. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. The embedded URLs and the nature of the heuristics strongly suggest a phishing attack pattern, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160884a489e3a2---ridefatakikunegovabubi.pdf In PDF document text
    • http://79.170.40.182/boothtastic.com/wp-content/plugins/formcraft/file-upload/server/content/files/160821de4a3e35---1684046393.pdfPDF link annotation
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607d73813637b---jowudalajuxebevowukonolu.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099f5b7afad0---29069983330.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/39189489146.pdfIn PDF document text
    • http://easyliveconstruction.com/ci/userfiles/files/depatatuzirigipokepaxezo.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/muzifoxige.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/5f4aot13f4g4cenfk5vnged21m/berozajilela.pdfIn PDF document text
    • http://toanlinh.vn/upload/files/23800138916.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/vuxomatusod.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/127b1fb85044908d3ea7730c6b99cf3a/votoxurox.pdfIn PDF document text
    • https://mindspacepsytherapy.com/upload/ckfinder_temp/files/20210528091559.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/60b919318d6ee497cc885cb905a4e853/notexud.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/21836602365.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/aff98a0f75ff9a94a809e4119d4fb88c/80963301445.pdfIn PDF document text
    • http://medicare-darmstadt.de/bilder/UserImages/file/1632641402.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/imdtrmq53jshpm00trfhoppns0/lumove.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/df170469144d10ff19d8aef4aa7ebcad/korazujesilejadapom.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160801f5d42082---61096278250.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16087ae98086b4---45988794851.pdfIn PDF document text
    • http://sonkertrail.org/clients/9/92/9260a3c387aed4615f72c72c3a1da295/File/17352561754.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607dbfb2e6f18---34369123375.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/55c0ec72acf93755e0df8f135f9d8635/96455988381.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=peat+moss+for+overseedingPDF 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_off0000f3f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C0A 18044 bytes
SHA-256: 32e62b17d81d40178ba67d52df5ed4a3b9950fa7678e8cc783f5beec1d3386f9
font_02_sfnt_off00013b41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B41 10720 bytes
SHA-256: a8247b2c1c6ba78f11e4bdb9435afcaed660f39e1640fe72e5a51050f1d2afbd