Malicious PDF — malware analysis report

Static analysis result for SHA-256 a44f134489386572…

MALICIOUS

PDF

81.7 KB Created: 2021-06-27 08:42:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 097a2ab29517386fe048cd949f92743f SHA-1: 1d726714c9c7ca497d42a671cc150108f8ded06e SHA-256: a44f1344893865725899d17d99d1e4b0bad04339768372371701a7b36bcbc79c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it functions as a link farm. The presence of these links indicates an attempt to direct users to potentially malicious or phishing websites, aligning with a spearphishing attachment tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 https://cructi.ru/uplcv?utm_term=4.45+kg+in+pounds+and+ounces
    • https://clumba-indoor.ru/files/files/66090539251.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/023c3457de99df13f45e431c26b3d34b/15035095484.pdf
    • https://www.ideaklinikbursa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160793cafed175---kiruponujitivef.pdf
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607eefbceb893---32291246752.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3d7ac3f39---nuxopofewogagodizonipud.pdf
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/cc53v4le5b1vcvpof7f6brt095/kitikub.pdf
    • https://cicadit.ro/UserFiles/file/xajilafin.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a60fb7a4b37---pufexudaxelebulasaxidadej.pdf
    • http://nomorecpapmachine.com/userfiles/files/29925645782.pdf
    • https://by-express.com/upfiles/editor/files/20370065006.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f90e2ab663---nuxazalukizezotuputof.pdf
    • http://www.agenbenangbandung.net/file/28747902490.pdf
    • http://argyler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607593af09949---93443846372.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/c1d5bc0e1754b776805cacb420545d93/devexizisazuwegutolitamef.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084675e1ba13---64302098626.pdf
    • https://artbynela.com/uploads/file/90568999679.pdf
    • http://barcelonasixtytwo.com/userfiles/file/56864448264.pdf
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b7706fe422b---94743609198.pdf
    • http://charivne.info/images/file/68390608232.pdf
    • http://telekommarketing.com/firme_data/files/vivevinomumebalixepa.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3543e00bf7---vadeze.pdf
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/2fc1a3ddb8de624febeddae1347bda05/kuxuxutemapenogirikip.pdf
    • http://kapsalonindex.nl/images/uploads/32507002651.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16087235c95ec1---puvusefedubarewosuvamilag.pdf
    • http://cuspsurgeons.com/userfiles/file/31017768002.pdf
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce8cfb580c---farawe.pdf
    • 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_off0000dd18.bin
a87f5c47232e9bb6a1d1ae84475ef2ac9ec92e1c1320dcc3ab222d8c1d5b156c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD18 16632 bytes
font_01_sfnt_off00010862.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10862 16792 bytes
font_02_sfnt_off00012079.bin
6b14a01b849d1fcff26a65927c5bbb203950e9b7cfa2ebd4fd8254ad0827cf1d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12079 10816 bytes