Malicious PDF — malware analysis report

Static analysis result for SHA-256 fff0b6b4f04a9ca1…

MALICIOUS

PDF

80.8 KB Created: 2021-09-20 17:47:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1a8cf24e07681865027aa653ad5eade9 SHA-1: 39e970586d73529c348ed2a02f22af3954f9dc6f SHA-256: fff0b6b4f04a9ca1d0d5227830b6f07e70acb58f40e1b33d0c9bf839f3856f70
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting domains, suggesting a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and heuristics indicate it's a link farm potentially used for malicious redirection or phishing campaigns. No scripts were extracted, but the structure and URL distribution are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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://slotpt2.com/contents/files/2457132379.pdf In PDF document text
    • http://dayou.tw/uploadpic/files/202109100553153348.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/qb4at0pqr59jan0spdp8kktm0k/sefivutaxigugimemagit.pdfIn PDF document text
    • http://tuclubcr.com/campannas/file/pumidinuwudovo.pdfIn PDF document text
    • http://vom-ragnaroek.de/uploads/file/79399768100.pdfIn PDF document text
    • http://kaies.cn/upfiles/2109160151207264443sxmcf.pdfIn PDF document text
    • http://a-b-i-s.net/layout/bilder/file/53401503754.pdfIn PDF document text
    • http://fqcycpa.com/jingkelun/userfiles/files/20210915211151.pdfIn PDF document text
    • http://bachtungcompany.com/upload/files/62872006878.pdfIn PDF document text
    • https://aecvfcom.nrgence.com/upload/userfiles/files/38350168418.pdfIn PDF document text
    • http://zamgph.com/uploads/file/112151551264.pdfIn PDF document text
    • https://lean-ds.com/upload/editor/file/dijofu.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613566468333e---subinelokejami.pdfIn PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/8489417903.pdfIn PDF document text
    • http://artgrafika.cz/userfiles/file/rowiwatemiwoziziwugimafub.pdfIn PDF document text
    • http://normel.org/files/upload/file/winezupivakuwes.pdfIn PDF document text
    • https://lhorizon.ca/uploadHorizon/file/kewitibu.pdfIn PDF document text
    • http://thaicockstar.com/ckfinder/userfiles/files/rulekaripezokikixajir.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/5c1be5139efb8f000130654823e277a1/63516535546.pdfIn PDF document text
    • http://kantipursecurity.com/userfiles/file/mopafivifijovakif.pdfIn PDF document text
    • http://kbfrutos.sk/images/_file/91581984856.pdfIn PDF document text
    • http://villa-carlshorst.de/sites/default/files/file/xuzegoxikubinagetuxodix.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=harry+potter+and+the+deathly+hallows+streamPDF 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_off0000d7e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eff3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF3 17580 bytes
SHA-256: 55f8c3db8201b8e3be5c86e7e14d673f6349b2d4a0ad62095bda62635d2c18d1
font_02_sfnt_off00011d22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D22 10756 bytes
SHA-256: 1ffe1768f7aed48c6ecff99ac683ee97eabbdfe3304624dd00145e6063f68674