Malicious PDF — malware analysis report

Static analysis result for SHA-256 97e515eb628b9449…

MALICIOUS

PDF

82.0 KB Created: 2021-09-07 18:36:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fa3c2c7a87a5b6607464f5e404984697 SHA-1: 2723b7acc8c78936972e7c4115274f4e4e27dcaa SHA-256: 97e515eb628b9449fe7a0384a265d125096cf0d47d0e3afa615e0643448846ce
96 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to other PDF files hosted on various websites, many of which appear to be compromised CMS uploads. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to manipulate search engine results or distribute further malicious content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://albino-pitti.com/pub_img/file/riduluti.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce565224ff---turuzometubopinew.pdf
    • https://koratspring.com/upload/file/sejuxawowife.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16079efff7b341---tetipuxijemefaf.pdf
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/3f479eb6fab5e25871944d7579ff2ad7/tigikatoponemux.pdf
    • http://taxicityplus.ru/userfiles/file/dularap.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/s1jq59q916jj5rb9ad20n3md56/zafitekoxid.pdf
    • http://delve-cr.com/uploads/2034671133.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/c29b3f1f14faf4a37ade24f8fb93da72/31800951662.pdf
    • https://olivierdaulte.com/ckfinder/userfiles/files/10180333606.pdf
    • https://samarpanbharat.org/trila/userfiles/file/77602049416.pdf
    • http://sbstroy53.ru/img/files/dogasidapemitadu.pdf
    • http://younewstoday.com/task/userimages/file/sepunexuxorezo.pdf
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160dc86aab98c0---41785890839.pdf
    • https://tyeetomsfishing.com/userfiles/file/miragerun.pdf
    • http://georgeandmaryjones.com/clients/f/ff/ff66b05efb8f16ea353d8e6908bb1429/File/78672178457.pdf
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a10dd41e5de---34618328358.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/ccb1e13deae58a4592c37a6946b66faf/87432127309.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bc0eb661b8f---pimesu.pdf
    • http://theclelandgroup.com/img/upload/file/risefutodojubu.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/14e04174ee02732d23f11c8f6ba9d133/68106368552.pdf
    • http://dorp.pl/userfiles/files/14943252561.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=rapport+de+mission+de+travail+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d76b.bin
c527d89f259eb21ccfd8f466056ed0d003776e48423f14b3ac1f22bcb21af700
pdf-font-stream PDF embedded font (sfnt) at offset 0xD76B 10768 bytes
font_01_sfnt_off0000f038.bin
8a55fb2e75fb027b7d3772f188a037021b0dd29521727b1748ffd7bfe0ef618e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF038 19824 bytes
font_02_sfnt_off0001222b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1222B 16792 bytes