Malicious PDF — malware analysis report

Static analysis result for SHA-256 49b9b5799d98a279…

MALICIOUS

PDF

85.9 KB Created: 2021-09-19 20:53:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 02a73aa2db816468d989548a949248c5 SHA-1: 3ecf9449ddb6f0777f0257dd309ee8d04907d468 SHA-256: 49b9b5799d98a279a294ba1ac80e00d58398a4a5e44304ebae1edccbf89ac604
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a significant number of external links, many of which point to compromised websites or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery through these links. The embedded JavaScript, while not fully analyzed for specific actions, is a common vector for exploitation in PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nuraski.pl/wsg/userfiles/godowidezuk.pdf In PDF document text
    • http://opsir.eu/files/file/4272128906.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/ncaqto2vkcq5p0jk4lvcc0c6dk/44478174913.pdfIn PDF document text
    • http://proxima-design.cz/files/file/26410315969.pdfIn PDF document text
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/padoxebezetad.pdfIn PDF document text
    • https://taxfirma.com/userfiles/file/vebemupijavenamatanis.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/mofozujaligebotebitasi.pdfIn PDF document text
    • https://oklogistic.lv/upload/file/bojopibedatodofoxozojale.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/duzininigudez.pdfIn PDF document text
    • http://cameranichietsu.com/luutru/files/3879642974.pdfIn PDF document text
    • http://wxbeimei.cn/upload/ckimg/files/202109051926252869.pdfIn PDF document text
    • http://girlstown.org/files/js/ckfinder/userfiles/files/biweratofifaxupukekotevag.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/161348feb83739---27471813921.pdfIn PDF document text
    • https://websbag.com/uploads/files/pibakawimelo.pdfIn PDF document text
    • http://grafichesirio.com/userfiles/files/sefofeloritifuvo.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/7df52652ba36608f2f3c95e9258c03fb/6855861288.pdfIn PDF document text
    • https://esportenerd.com/app/webroot/ckfinder/userfiles/files/wiloxejabudolutumuvun.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140b6f875740---17007480354.pdfIn PDF document text
    • https://anakmeong.com/contents/files/dopugaropi.pdfIn PDF document text
    • http://studioarclab.eu/userfiles/files/82909262175.pdfIn PDF document text
    • http://pallenberg-busreisen.de/uploads/files/18135413001.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/2ff50ae0188b1cd2be8aa2b7d0b46552/13711615274.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/39214458338.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/53804935492.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=the+best+epub+reader+for+androidPDF 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_off0000ec13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC13 17324 bytes
SHA-256: 02a1539c51cfc77e158f5bc32c739e535224e82add45aa27d7a83c8d528c415c
font_01_sfnt_off00011917.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11917 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001312e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1312E 10752 bytes
SHA-256: d8bb18a2549edcfa2f7cba5a88069e683f5b4ba0aba0c59f239e844caa43b104