Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc22cd8d98e53920…

MALICIOUS

PDF

69.8 KB Created: 2021-09-30 23:06:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 14fb98a4d4111148d96602a347862fcd SHA-1: 9cfac954ea267d0e5a4a0c7e3b875e77ae3ef043 SHA-256: fc22cd8d98e5392019d76f3dd467ecbee6162581135dda725be4c9e981dadd20
96 Risk Score

Malware Insights

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

The ML classifier and PDF heuristics strongly indicate maliciousness, identifying the document as a link farm. It contains numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute malware or host phishing content. The primary attack pattern involves luring users through potentially deceptive content or SEO poisoning to these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://taxicityplus.ru/userfiles/file/wapedefit.pdf In PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/87543390748.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kuwezuno.pdfIn PDF document text
    • http://les-dvorik.ru/userfiles/file/38778648194.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/66117310a3b8a19a9f5ddb6ca85f964b/62145389122.pdfIn PDF document text
    • http://olympiad-bigben.ru/ckfinder/userfiles/files/46820971924.pdfIn PDF document text
    • http://nuocmambason.com/upload/fckimagesfile/6a6eab8845d69cecdc88952a83e76c8d.pdfIn PDF document text
    • https://trungtamgiasuhcmmq.com/uplaod/quangtri/files/10556688331.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/161430b60eb6c7---narosiliwimezipimonufol.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/pumurepuvebidinaxadidolep.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16137463df0847---xaxufigifurinonatup.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/vozunazilaxo.pdfIn PDF document text
    • https://hargagila.com/uploads/image/files/rixajakerug.pdfIn PDF document text
    • http://tonghuichem.com/upload/files/lomoporusom.pdfIn PDF document text
    • https://giasidaily.com/uploads/userfiles/file/54477213788.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/edbc88c4752aa1d00a2ad818880d5109/83365109460.pdfIn PDF document text
    • https://kristinanamaste.eu/files/61652698377.pdfIn PDF document text
    • http://thaihotelsale.com/FileData/ckfinder/files/20210912_75226CCAD8830F55.pdfIn PDF document text
    • http://nagyberki.hu/sites/default/files/fck_uploads/file/21202247272.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/62724590756.pdfIn PDF document text
    • http://countryclaim.cz/userfiles/file/77687658269.pdfIn PDF document text
    • http://circolosilverblufitnessclub.eu/userfiles/files/patepobiteximonawagojapas.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132282fecae1---38637341125.pdfIn PDF document text
    • http://gsprojekt.eu/userfiles/files/57716208283.pdfIn PDF document text
    • http://vattuxaydunghl.com/userfiles/file/42807688128.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=apk+fix+fortnite+iosPDF 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_off0000b222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB222 16032 bytes
SHA-256: 431c399372a5be52e2000ad2c6020a46930ae51dae6df9f0c68b2a9e14f39170
font_01_sfnt_off0000da81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA81 10320 bytes
SHA-256: d895bc67ca1a522d0cad93001c93a01672616c87a110799e0e9768d229e4da98
font_02_sfnt_off0000f1f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1