Malicious PDF — malware analysis report

Static analysis result for SHA-256 71bea9e226af4606…

MALICIOUS

PDF

90.6 KB Created: 2021-09-04 05:43:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e3282d9a4ae62eed0535afa9473379d9 SHA-1: 76b9d9d0566c4a12cc3946345304707a73ec08c7 SHA-256: 71bea9e226af4606e5bcbcffe39e5cbb4a20a4ca2964204dfef55f1303754517
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It functions as a link farm, directing users to numerous URLs, several of which are hosted on compromised WordPress sites or disposable domains. The presence of multiple PDF link farm heuristics indicates a deliberate attempt to obscure the final destination and potentially distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://megalabsrl.it/userfiles/files/20476478548.pdf In PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/darigixunixa.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca70b688e4---zetijunodawujikasopa.pdfIn PDF document text
    • http://wonikqnc.com/upload/editor/file/1625359969.pdfIn PDF document text
    • https://ohcsi.com/ckfinder/userfiles/files/76268154675.pdfIn PDF document text
    • http://adwokaci-pila.pl/userfiles/file/furebigiwiwetolepokon.pdfIn PDF document text
    • https://likeevent.it/writable/public/userfiles/file/jomevibiwopewulolegopa.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16087a9e577e2a---2040665148.pdfIn PDF document text
    • http://daotaonhaccong.com/uploads/userfiles/file/tavagonubeguwoluwugedof.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e8bfd4e9d27---wilokafajomabo.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610b4c74965ca---18779547652.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608c892ab7a25---zavon.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/b9mpln3hvaei72u2rk48s7i03b/xixabadivarifebubo.pdfIn PDF document text
    • http://zgic.ru/!upload/files/fubixuta.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/caf523861296d0ebdffdeea9ccc6c6b1/bomafitajij.pdfIn PDF document text
    • http://thewesternmist.com/userfiles/file/rirolusotafipiral.pdfIn PDF document text
    • http://anoh.net/pds/userfiles/files/84631591619.pdfIn PDF document text
    • http://www.toeterloeh44.de/files/48047448481.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/18689066019.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/mamusuneno.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/foxunabozajefi.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe278fe08c6---giratikugexidabo.pdfIn PDF document text
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607198606eb39---11612813959.pdfIn PDF document text
    • http://sumbulefendiegitimvakfi.com/resimler/files/66349100394.pdfIn PDF document text
    • http://avvolodin.ru/upload/file/3068606773.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=lev+vygotsky+pensamento+e+linguagem+pdfPDF link annotation
    • https://rt9.rspo.org/ckfinder/userfiles/files/moserutulexakonog.pdfIn PDF document text
    • 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_off0000f545.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF545 20204 bytes
SHA-256: 203390232f22d3b319c3e5a8a1b5752ab00c86230c7245345aebdd669b8ba8cb
font_01_sfnt_off00012932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12932 11072 bytes
SHA-256: aac8b5cea1963615bf7f472bc10dbc84911270a939fb559904b8c4e6606f0509
font_02_sfnt_off000142d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1