Malicious PDF — malware analysis report

Static analysis result for SHA-256 c957157cfc5389bc…

MALICIOUS

PDF

84.0 KB Created: 2021-09-18 19:26:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: c5b67444296dbb744044da8a596d119c SHA-1: 573d7d47e9c426178db0915a2f60639dc5c58e4f SHA-256: c957157cfc5389bc0f1956ca499cbb08b554b744e80ddc6cff87ad053e48bc7b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites. These links likely serve as lures for phishing attacks or to distribute further malware to unsuspecting users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16135ceeb511e0---mipadunewukuxegedex.pdf In PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/ed7aa4ef6eda6f8197c360b3ff071f9c/74545626983.pdfIn PDF document text
    • https://virtrade.gr/userfiles_lybo/file/tufexepex.pdfIn PDF document text
    • https://akemi.ro/hirek/file/gifinuwiner.pdfIn PDF document text
    • https://espiber.cl/images/uploadedimages/file/76275032819.pdfIn PDF document text
    • http://fpole.ru/sadm_files/rutaxifudovadefabesof.pdfIn PDF document text
    • https://desco.scp.hr/files/82261638718.pdfIn PDF document text
    • https://bititechnika.com/uploads/file/palukozosidawibureliba.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/161448663ef672---59922034388.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/18040445440.pdfIn PDF document text
    • https://mavachhaiphong.com/upload/files/84632843602.pdfIn PDF document text
    • http://dedanskecasinoer.dk/userfiles/file/zozagesuzo.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/161302f8e174ec---funulekuj.pdfIn PDF document text
    • http://tfforming.ru/d/files/30491347003.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/e2fcf7187aa54ad64ddc031114ead1a8/sanano.pdfIn PDF document text
    • http://www.andreapondika.cz/file/68895712815.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/1316808809.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16139064f11f41---kidategexumavunedikukepi.pdfIn PDF document text
    • http://hani-bee.com/userfiles/files/fumogezojajafepepumikopon.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/566a06f2ee12b404365d8ac867d8dc46/1024261976.pdfIn PDF document text
    • http://boldogelet.hu/media/53385204132.pdfIn PDF document text
    • http://goodfortune.hk/UpLoadFile/file///21561163591.pdfIn PDF document text
    • https://gjbuyerbroker.com/userfiles/file/volotixepalebe.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/tetumimupe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=sunny+hindustani+singerPDF 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_off0000e1e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E4 10648 bytes
SHA-256: a02000fc1861082753477a1cf56d53975fca2c7bb3a46ef94ad37c4c22ad3ffa
font_01_sfnt_off0000fa0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA0A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001121c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1121C 18588 bytes
SHA-256: 8eb6e9b92c14603f82b284ee2f39e7bca12396c7df1c994b3282dac44eccfe01