Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a850d2c633d8108…

MALICIOUS

PDF

85.8 KB Created: 2021-09-17 15:01:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d47c702d406115057071d23c7f4b04b7 SHA-1: b60b274a99dfc673ed7e8abe76ecae6065263f18 SHA-256: 0a850d2c633d8108545e96513ccc3220714a50f772da3c038c250d1dab0d65d3
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to potentially compromised or disposable hosting, characteristic of a link farm. The presence of embedded JavaScript, though not directly executed in this static analysis, suggests potential for malicious actions. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm or content distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://albarossa.jp/js/upload/files/43115138071.pdf In PDF document text
    • http://3qbuy.com/CKEdit/upload/files/87881937421.pdfIn PDF document text
    • https://eprobatdz.com/ckfinder/userfiles/files/88606367562.pdfIn PDF document text
    • http://school15-tyumen.ru/f/dumabopel.pdfIn PDF document text
    • https://pindimana.in/uploads/file/vabomazib.pdfIn PDF document text
    • http://tantusmarina.com/UserFiles/file/jarevomufufadokijigomori.pdfIn PDF document text
    • http://burattinojatek.hu/userfiles/file/45017570542.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/puwiwep.pdfIn PDF document text
    • http://yachtandgulet.com/userfiles/file/kisekuvugomagula.pdfIn PDF document text
    • http://homeopathyhk.com/files/73735337893.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/30164631226.pdfIn PDF document text
    • http://menifee.hanasushichoice.com/uploads/files/tefuselixi.pdfIn PDF document text
    • http://3m18.com/images/editor/files/89587366558.pdfIn PDF document text
    • http://csc0351.com/userfiles/file/20210906011608_jknfyr.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/mab8ie7ou1bganedhagtfobfpt/saxiri.pdfIn PDF document text
    • https://mraos.com/web/userfiles/file/nemegobosudimekoraw.pdfIn PDF document text
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/2q8qh7b968qpfe4i8hcjhoj7p0/romazagazevawakinifemora.pdfIn PDF document text
    • http://wlpp.net/images/blog/file/44707623049.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///46537689557.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/51727069057.pdfIn PDF document text
    • http://aj-freight.com/ckfinder/userfiles/files/64405390331.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/161321a5e97074---sakisewovatoxe.pdfIn PDF document text
    • http://www.portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/67062903799.pdfIn PDF document text
    • http://abwrichmond.com/uploads/files/70644221556.pdfIn PDF document text
    • http://nhakhoauytinhaiphong.com/upload/files/rupaxenuvagutiwibo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=best+video+recovery+app+for+android+freePDF 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_off0000eb4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB4E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10360 17368 bytes
SHA-256: baf614fd23087e0af453edd08e2705a1f377f8628431ca5c50aa3c6b54a1a7ec
font_02_sfnt_off00013075.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13075 10800 bytes
SHA-256: 575ab468d333a11f81f3a6198283ce5606f277ff8ab1f53cb2d3644d9f3485ea