Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff7a4bdd2661b88a…

MALICIOUS

PDF

68.2 KB Created: 2021-09-24 23:13:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 01d0795b64d3a0322aed813938f3f6a1 SHA-1: 99c883e9545ee2a025bf75383a326f389bae7775 SHA-256: ff7a4bdd2661b88a1bfec8fa4d864b80b00f95e9b31dd17d425c895d84552ebe
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The ML classifier strongly indicates maliciousness. The primary attack pattern appears to be directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://irlanc.ru/uplcv?utm_term=trig+function+equation+calculator PDF link annotation
    • http://pomocnaukowa.net/Upload/file/bidoz.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/16663779292.pdfIn PDF document text
    • http://duda-tech.pl/dudatech/upload/file/69930985839.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/155c2f2f0aff8ebcf69b47670ab45698/45117631605.pdfIn PDF document text
    • http://dryoucosmeceutical.com/userfiles/files/75531314648.pdfIn PDF document text
    • http://wildpflanzen-planung.de/file/13051844283.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/3486345873a3a1f6ad8eef2e1bf40660/24796960.pdfIn PDF document text
    • https://simon-daulte.com/ckfinder/userfiles/files/powesetexilejoxoboketeji.pdfIn PDF document text
    • https://clubelsendero.com/img_pag/file/wolasavibesuj.pdfIn PDF document text
    • http://sofia-es.tokyo/yamituki-n/uploads/files/8376165900.pdfIn PDF document text
    • https://atvatextile.com/upload/ckfinder/files/vuxubofok.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/udks3i7t363t775bjb69u1kpnu/80579866257.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130ceedbb19d---32358717606.pdfIn PDF document text
    • http://vasset.bg/userfiles/file/zavafinevidugumo.pdfIn PDF document text
    • https://ans5680.preneed91.com/upload/files/89382070687.pdfIn PDF document text
    • http://93564497.com/userfiles/xepunotemumobo.pdfIn PDF document text
    • http://viacaosaopedro.com/www/js/ckfinder/userfiles/files/53795593363.pdfIn PDF document text
    • https://lixtech.com.tw/ckfinder/ckfiles/files/13288290094.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/63901943508.pdfIn PDF document text
    • http://parilka.by/var/upload/file/torufodim.pdfIn PDF document text
    • http://zonweringnederland.com/ckfinder/userfiles/files/7024820539.pdfIn PDF document text
    • http://kammed.com/userfiles/file/bumedesagejak.pdfIn PDF document text
    • 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_off0000ad0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD0E 15176 bytes
SHA-256: d581be2869ab7c544011cd3062d59c13a090b5ddb84f35a17234aa1666802800
font_01_sfnt_off0000d369.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD369 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB80 10552 bytes
SHA-256: b4f1939f1e85e46b8176dff5692e2aed581e6a08b67c1ac8246af9d070a83fe8