Malicious PDF — malware analysis report

Static analysis result for SHA-256 4229f7b5cd2c040d…

MALICIOUS

PDF

79.6 KB Created: 2021-09-16 20:03:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ef4b308c09ea637c07c9463e45c0a359 SHA-1: dcc084a16638039164c40068a38941c2447bdeda SHA-256: 4229f7b5cd2c040d6ec0a6ee56001696ac4fc0ad2388571d06a48389df42ed53
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content or engage in SEO poisoning. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, and the document body was unreadable, so the primary evidence comes from the URL heuristics and the ML model.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://dtpokebar.com/uploads/files/nazixinuzavigasolelodu.pdf In PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210903_1904ED83DCDE1B6E.pdfIn PDF document text
    • http://dpnovelty.com/upload/files/67912637285.pdfIn PDF document text
    • https://synodradomski.pl/userfiles/file/bolanixudibobeje.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/pajim.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/76154081585.pdfIn PDF document text
    • http://fsgpj.com/upfolder/e/files/20210916190500.pdfIn PDF document text
    • http://zeroseistudio.eu/userfiles/files/19756259193.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/e2a555706e7c492fa3173c6cdf7177b3/kiliveselunu.pdfIn PDF document text
    • https://millvalley.com/wysiwygfiles/file/taloveveditevenuvedoki.pdfIn PDF document text
    • http://niengrangchuyensau.com/upload/contentFile/file/33223127689.pdfIn PDF document text
    • http://baocaosudanang24h.com/uploads/image/files/tusezafu.pdfIn PDF document text
    • http://hasyo.net/files/file/90834203883.pdfIn PDF document text
    • https://goodnest.info/tctt/sites/aaa/file/50023771193.pdfIn PDF document text
    • https://songhong-thudo.com/img/files/61898791546.pdfIn PDF document text
    • https://mabuksusu.com/contents/files/begulozexetipixiworer.pdfIn PDF document text
    • http://cichanski.com/Upload/file/najimu.pdfIn PDF document text
    • http://heibldr.hu/FCKfeltoltott/file/36140565380.pdfIn PDF document text
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lilekapobafusipazixukos.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613b159e8e140---90014022949.pdfIn PDF document text
    • https://songiadahoaian.com/upload/ck/files/vidifimatu.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/161304cf816239---63654156063.pdfIn PDF document text
    • https://uleiuri.ro/userfiles/file/pureruwesubajo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=clouds+and+sheep+apkPDF 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_off0000d0c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C4 19072 bytes
SHA-256: 551e948728f411d255d3610f0eab070721d44eca198f53045b7d580098ee803c
font_01_sfnt_off00010174.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10174 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001198b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1198B 10424 bytes
SHA-256: 2347ffe2d1bd3797396763f92932a98875a5ae9c19173de7e4f1b5acdb8809ce