Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbb8950f157aea80…

MALICIOUS

PDF

89.0 KB Created: 2021-07-05 23:43:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 0174b2d981e4167252c5f84eb111af81 SHA-1: ae5aa256d95d5c122e474d9bc5ce624382762466 SHA-256: cbb8950f157aea80f765dff841a94246e021e262fa16479b4a14111230f0f756
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links pointing to various websites, many of which are hosted on compromised WordPress installations. The 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics indicate a pattern of using these links for SEO manipulation or to host malicious content. The ClamAV detection and ML classifier further support its malicious nature, likely as a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/844c7ee3788b48d93d847d58e15d8887/79352375922.pdf In PDF document text
    • http://kawoka.com/userfiles/file/kuzogefotomuwedinelexolo.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/7eeb68cee675e930f654c5e3bf8b911a/daropovuf.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/6d4d47ad378e3bf01939323c1e50907e/79864279645.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160bbcc436aa80---wuzaturizuguwikovunir.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/62233702709.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/ojclroud1refhoe0v53glhu4ms/jupebonapubewebodibat.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16087ff10d6ed9---55592110319.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/nnean8oett1ccnv4kl0tu19b04/tilixikeb.pdfIn PDF document text
    • https://afayl.com/userfiles/file/doforebezonurikaweb.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/wirapuxalev.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606efdd0048ff---48112912828.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbe7a1db76---27020614705.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b40b298025f---81515590101.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5877953137---gudugokizule.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/19875904736.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073784052b25---28572410533.pdfIn PDF document text
    • https://dm288.com/slicice/file/litamukawamupuwakak.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/79427846391.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be71b6c8f71---mirisajo.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-6-13/20210613050154557842.pdfIn PDF document text
    • http://0930actress.com/files/files/gazukugos.pdfIn PDF document text
    • https://ajitcoatings.com/uploads/mitubugepamuw.pdfIn PDF document text
    • http://woorymart.com/userData/board/file/kuneb.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afde9fc5c16---lasididerojomofiwej.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/08c2d36c374c75a37780ddbca748f8cd/turidasarugadatuxomi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=rhi+refractory+productsPDF 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_off0000f7d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D8 18124 bytes
SHA-256: cef83bdc84617240baa0e29ed9aa823820241034b357fe076add685802db2c83
font_01_sfnt_off00012583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12583 10824 bytes
SHA-256: dec2a21ed0a5c422cee4c2f6253015ca3b14c0af87da429b298ec1f59ddb27e3
font_02_sfnt_off00013ead.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1