Malicious PDF — malware analysis report

Static analysis result for SHA-256 fec3803d2f8ba49e…

MALICIOUS

PDF

81.7 KB Created: 2021-09-16 12:10:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 994292234acff8f4045d95617dffbd64 SHA-1: 26b791cfb8818730fb388d337376ddae99c5f84d SHA-256: fec3803d2f8ba49eac2b916ce8139e67b5f8db69d03ea0ea0b243a53919090ee
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and other domains, suggesting an intent to redirect users to phishing or malware hosting sites. The presence of these links and the nature of the hosting domains strongly indicate a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://rockycheng.com/ckfinder/userfiles/files/48231396828.pdf In PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613986210b177---ketulesakuzekuzebaworumab.pdfIn PDF document text
    • http://gesgo.de/userfiles/file/fekijitusirukit.pdfIn PDF document text
    • http://streathamtaxi.com/survey/userfiles/files/5768330863.pdfIn PDF document text
    • http://mevlanaasm.com/resimler/files/pasavukopirinanubatobowix.pdfIn PDF document text
    • http://findusafranchise.com/files/files/70572578984.pdfIn PDF document text
    • https://igk-lilienthal.de/downloads/gukatof.pdfIn PDF document text
    • http://demkapi.com/resimler/files/10181042090.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/3613c76fa561bf05dc68d75041d97157/72029449675.pdfIn PDF document text
    • http://vititanon.com/user_img/files/dojevofimifarubetimu.pdfIn PDF document text
    • http://chaukitchen.com/uploads/files/gikib.pdfIn PDF document text
    • http://mfcpavpos.ru/file/38610377645.pdfIn PDF document text
    • http://rfaaa.com/UploadFile/file/20210916035117591.pdfIn PDF document text
    • https://hygradeinsulators.com/images/uploads/file/82283430548.pdfIn PDF document text
    • http://giustizianuova.it/userfiles/file/varogopuf.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/dunoxotepuzironosejuba.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/95729022789.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/77940106045.pdfIn PDF document text
    • https://www.znackakvality.info/files/bunoziwazuja.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141da068d510.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/sakazolutimipara.pdfIn PDF document text
    • http://kxxbs.com/uploadfiles/file/a/71946819476.pdfIn PDF document text
    • http://www.srijonihealinghome.com/fckimages/file/vifenagukanowijulisoso.pdfIn PDF document text
    • https://www.vasutaszeneiskola.hu/ckfinder/userfiles/files/muwedexo.pdfIn PDF document text
    • http://pitchdecor-construction.com/user_img/files/kifigekubiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=names+of+smartphone+brandsPDF 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_off0000d653.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD653 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6A 10744 bytes
SHA-256: eec3fca1844b880a98a36d11e6e24542043b1f63ca8f64c00aa9b671fb03bbe3
font_02_sfnt_off000106ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106AD 19796 bytes
SHA-256: 07b3c90536d5ee18aa523dbe8a7c857a209715036f78239b1400f500641addff