Malicious PDF — malware analysis report

Static analysis result for SHA-256 96b4fcc8531211d7…

MALICIOUS

PDF

78.9 KB Created: 2021-09-03 23:10:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3609305ffec052e2897f70254f44c484 SHA-1: 13e16a9efa83a8c5b08cbd55d052b66eb1775ebd SHA-256: 96b4fcc8531211d79cf0c4fb153a13442a587ea60e8e95c33850a80edfd39825
96 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on various domains, many of which appear to be using compromised CMS upload functionalities. 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 0.9975

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 http://airconbank.com/upload/fckeditor/file/lazozilajoz.pdf In PDF document text
    • https://fo-prefectures.com/pages/files/63020496336.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/74370110163.pdfIn PDF document text
    • http://bm-shower.com/userfiles/files/jenoluxunibo.pdfIn PDF document text
    • http://www.velkoobchod-man.eu/ckfinder/userfiles/files/fumofusi.pdfIn PDF document text
    • http://thaisomboonautopart.com/userfiles/files/xesuzipali.pdfIn PDF document text
    • https://divetechmarine.com/contents/files/xiwalezulopavubutarula.pdfIn PDF document text
    • http://yulintimber.cn/d/files/36411545914.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160fe59c45fc22---22555356247.pdfIn PDF document text
    • http://elementsgogreen.com/userfiles/file/75255098504.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16080586b2088d---56724912496.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/68175939188.pdfIn PDF document text
    • https://tw-itemaos.com/ckfinder/userfiles/files/84754880804.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e48609f4a1---dakunesetutoza.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b9ec1d302a6---siresoburararemow.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1612b254e87852---59119743164.pdfIn PDF document text
    • https://szallas-karpatalja.net/upload/jodusanigojuxo.pdfIn PDF document text
    • http://valeneighbors.com/userimages/77491729119.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/munipenopuja.pdfIn PDF document text
    • http://buyyoutubelikes.com/ci/userfiles/files/77977899348.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/lekezewotuxemowixowotode.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/61145914097.pdfIn PDF document text
    • https://edarky.net/data/file/zobuxetubagojabopomiv.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/cd44423ab321f045f276758430541d6a/57491045085.pdfIn PDF document text
    • http://www.atccs3.it/atccs3/fckeditor/editor/ckfinder/userfiles/files/gobemirax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=rudali+summary+pdfPDF 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_off0000ce6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE6C 10464 bytes
SHA-256: 891d5546af1b0466644ce907a86718136a60ceafc229960749c8a8f3c0dca124
font_01_sfnt_off0000e624.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE624 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE36 18200 bytes
SHA-256: 13fecf7ed109c709f2bb35bd609bb1b7bada2fae201fbd0ca98980f3c1b480a4