Malicious PDF — malware analysis report

Static analysis result for SHA-256 c19f81fb43e594b2…

MALICIOUS

PDF

76.5 KB Created: 2021-09-02 01:20:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 42df720026d5c665b6cf76d90295e4f5 SHA-1: 5cde364ea4e3069da7744e5a4a15dea13d68ea38 SHA-256: c19f81fb43e594b21f5c99895cd6be00f3cce41ce17092a441a7877dcde29279
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to numerous distinct hosts, many of which are hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 http://etcad.net/np/upfile/file/mefojenuxikepap.pdf In PDF document text
    • https://designclarf.it/file/70546058510.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b310a57ec93---jozebexeden.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/jakafamixekelut.pdfIn PDF document text
    • https://lasanisports.com/files/tutoka.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/b6a025a9eb985febdef9f4527b2421b7/gasefebuvewamigafepojewux.pdfIn PDF document text
    • http://spiregene.com/image/files/20210703_070427.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cdb8b6bd53b---98823151183.pdfIn PDF document text
    • http://premium-h.info/files/files/tulisamudoloz.pdfIn PDF document text
    • https://n-v-v.dk/userfiles/file/19222959324.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/77536f72d9ee23c109f76558d45fa662/95510443996.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a189c70042a---34389309514.pdfIn PDF document text
    • https://secolink.sk/userfiles/file/80318578777.pdfIn PDF document text
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/12ee2b29d7fec463a4430e24aa49a841/takotola.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1624275046.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/files/dilixorunomar.pdfIn PDF document text
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/fce49d68bcdb87cf7fe0d740cbd7c925/kifimeteruzefi.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/19orgaej733nuc2ssjv1487vnl/xonenorodiwazazogovive.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/juguvupi.pdfIn PDF document text
    • https://local-atlas.ru/userfiles/files/38692742862.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16090c5be33b8a---dokino.pdfIn PDF document text
    • https://nhachoxebus.com/upload/fck/file/6571029679.pdfIn PDF document text
    • http://101eyewear.com/luutru/files/sugenunetato.pdfIn PDF document text
    • https://luminex.pl/upload/file/ruwokeviruwewazugavan.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1l3fmgc9vnorct8h39k4lf0nm3/1471112562.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=guardians+of+the+galaxy+2+123+moviesPDF 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_off0000c2ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2AB 11568 bytes
SHA-256: be116bf190aeca7724d47924a34e1499710a390bb8eac112aad4fe39744f884d
font_01_sfnt_off0000ddde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDDE 17728 bytes
SHA-256: 19f56cb5ec1863dc98975b74b025b2f671ebd4a0bae3b8271d084031b8d8e2f0
font_02_sfnt_off00010bbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1