Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb97644afec874a3…

MALICIOUS

PDF

89.8 KB Created: 2021-06-26 21:47:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 21aa065f642907f9e0cb00b43e08498d SHA-1: a29562c192e3687539220d36692fc9cd0b714107 SHA-256: cb97644afec874a378fdd4f7598f17a6a7ae78c03cb3ea9e4f39cf82b41b7e3c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised WordPress sites, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/df7c951dd12033adf3b1997b237ec1e7/63742213141.pdf In PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/115vsrfkovu9ih8b6bnd1tc0u7/30352266922.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/92259089942.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609b54b3413e8---jebajukokepigigixagepovu.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/36030561562.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aec0b51309---depobifofilidomubo.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef6457ae12---powewodoza.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/2csab8r73o0or91cjhgr676gb7/80777586420.pdfIn PDF document text
    • https://europartner2.pl/uploads/xiwujutik.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/nopobejapajanexevovibur.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/10f4aecf1a778bfeca8d26540d4f0b71/newujamewilojexerinabevur.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/ab208a61b9a628dda38491806cda1ecf/lowarutizageletijidasas.pdfIn PDF document text
    • http://whatdwellswithin.com/file/liwidisenulemopakotidiju.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b24e1e6d4---dewumener.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/8t0qbi3dsdulubp5r3vcmrvmcu/logowakirodelanujajitekid.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1fe701ed8---xusixenivugukulenixinagu.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a904f2e46e0---61628345145.pdfIn PDF document text
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/xokitegexujagakibemexirig.pdfIn PDF document text
    • https://schmitz.cz/res/file/zawukiwugexefemamep.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16080ace558bce---tuduwifukomagomi.pdfIn PDF document text
    • http://coinproject.com/userfiles/image/file/26915713492.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/iga2e14b8oromjt27ie9m86d91/19396451233.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae267b0a5a---73936886384.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/jnio9n34khvijgdnv884bsarip/74917718870.pdfIn PDF document text
    • http://www.fk-fudosan.net/app/webroot/img/userfiles/files/32801357728.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=chill+and+drivePDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f296.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF296 17748 bytes
SHA-256: 329c7bb5333cec9b9d4d1c1d82131bf442bf51b411bf6e86a11279f4d583cc3c
font_01_sfnt_off000120e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000138f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138F3 2368 bytes
SHA-256: 4b67441bb62db1440980ba9a2a5cf8e25deecb000c665bef1a9b2fb5b04c3868
font_03_sfnt_off00014371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14371 10056 bytes
SHA-256: 5e782b4ea25e5e6d1b1a3b021331e5b5166ef4ed6c7cd93c5ebe2874dc9ad775