Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7c1e5a2eb99796d…

MALICIOUS

PDF

81.2 KB Created: 2021-09-10 17:26:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 456e8382ec9e814f2aa7d58f5ce069dc SHA-1: f236f59f59ac35d0b49fc21447b57d09b258f674 SHA-256: b7c1e5a2eb99796dfe21067cb92baa0bde800729d96268489eb03c09172894d3
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The presence of a link farm suggests an attempt to distribute malware or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://simonkuehner.de/gfx/userfiles/files/73096586938.pdf In PDF document text
    • https://123natura.com/stockages/files/81000386051.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/7f5034ba0cc246ba5f2289809b629304/galowanirenisen.pdfIn PDF document text
    • http://kientrucsangtrong.com/plus/files/5912450418.pdfIn PDF document text
    • http://nuitsdartistes.eu/images/file/32742545157.pdfIn PDF document text
    • https://locoffice.ru/userfiles/file/lutanedixewefijat.pdfIn PDF document text
    • http://ckud.handysociality.com/upload/files/57245716443.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/vinavugomizoveloj.pdfIn PDF document text
    • http://westernmaki.com/uploads/files/53822459874.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/gokikosutoxuweboren.pdfIn PDF document text
    • http://nakakinpump.kr/fckeditor/upload/file/jofet.pdfIn PDF document text
    • http://zjgyuanhong.com/v15/Upload/file/2021981136282703.pdfIn PDF document text
    • http://portableandcool.com/files/files/80749682921.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/nopotoxu.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/161326b4a3021c---87378773031.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161324eab34eb7---wafiwibiwukogowifo.pdfIn PDF document text
    • http://qcfloor.com/userfiles/file/63199069280.pdfIn PDF document text
    • http://chemtron-vostok.ru/media/file/duwuzakirevamavud.pdfIn PDF document text
    • http://www.vegagastro.pl/upload/file/47100847807.pdfIn PDF document text
    • https://soalmatematik.com/userfiles/file/69781408509.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/98196982676.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/kenibofab.pdfIn PDF document text
    • https://renhedc.com/uploads/files/202109010855435099.pdfIn PDF document text
    • https://hanyauntuktesting.com/contents/files/zewoto.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/13349476726.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=netboom+hack+mod+apk+downloadPDF 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_off0000d78c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD78C 18016 bytes
SHA-256: d864900b94c160b51cbb4790cb1397cca1c52aed5ab271f151f725c89c5bced6
font_01_sfnt_off000106b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B0 10712 bytes
SHA-256: 2b4e1f22c68c69d49de041f28352933453bc718bfb5a00bd589ebf48d0e166d9
font_02_sfnt_off00011ef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1