Malicious PDF — malware analysis report

Static analysis result for SHA-256 16d3a81eb561b25a…

MALICIOUS

PDF

85.9 KB Created: 2021-09-21 00:45:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 46ecab14763aa2acb1c81f1c6ac289a1 SHA-1: 19909f1b95a6d4ea3d705d541757aa5eccf63041 SHA-256: 16d3a81eb561b25aade00d3abbdf3f4b25e5d8361a1eb00fb4c2b0e703a1ca88
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised websites or disposable domains, suggesting a phishing or malware distribution scheme. The presence of link farms and compromised CMS uploads indicates an attempt to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://cabsfromheathrow.com/userfiles/file/xibibapol.pdf In PDF document text
    • https://edubox.mn/uploads/users/0/files/wulopaxijulutu.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/99294043353.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/navim.pdfIn PDF document text
    • https://aluvioneschicamocha.sinecsas.com/ckfinder/userfiles/files/wasakizojupumoreweniza.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/kamebogobomewi.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614351b3835de---32089127345.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/342e2bcf08fd046bc2dd5ff99d670827/96135260144.pdfIn PDF document text
    • http://89928386.com/uploads/files/202109070359337311.pdfIn PDF document text
    • http://grawerlik.pl/userfiles/file/36240956802.pdfIn PDF document text
    • https://phuketwebstudio.com/ckfinder/userfiles/files/3954559580.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161400c95d52fb---16451272201.pdfIn PDF document text
    • https://viadagio.be/userfiles/file/pevuxa.pdfIn PDF document text
    • https://inprovitvenezuela.com/ckfinder/userfiles/files/52807159582.pdfIn PDF document text
    • http://wonikquartz.com/upload/editor/file/1631711243.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/4311d754ae1435858f145a3023fe8ab7/nunowipokulizujat.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/dijopowiderimukowibumo.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/jumobafederi.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/48756714580.pdfIn PDF document text
    • https://himalayanespresso.com/espresso_ckfinder/userfiles/files/jagunidu.pdfIn PDF document text
    • http://sunriverps.com/data/editor/file/fuzamokamud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=battle+realms+mobile+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_off0000e846.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE846 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010058.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10058 19072 bytes
SHA-256: 670b012d4a9b3f7b1a3dbf90245daad71142d8d4ffde12b3952291c38d988192
font_02_sfnt_off00013202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13202 10600 bytes
SHA-256: 46a29d36c9587be50ea7554ed2fcafcbe135b6711676399e11337ea724d2605f