Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8b38eaf3aa8f0ae…

MALICIOUS

PDF

76.0 KB Created: 2021-09-20 09:06:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 7c2b40fc3ec8d9b0de1beaf06756378e SHA-1: 12e48c8c11980b16001b6cfd7379a3595d5b3a08 SHA-256: f8b38eaf3aa8f0aead183e763f8670fc1a40f6e1d5c49c15012c62e986911a37
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on disposable or compromised domains. The presence of ML and ClamAV detections, along with the heuristic findings of a 'link farm' and 'compromised CMS upload link', strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to malicious sites, aiming to trick users into downloading further malware or divulging sensitive information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • 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://crysiq.ru/uplcv?utm_term=five+nights+at+freddy%27s+free+download+android PDF link annotation
    • http://co-wemart.com/careeruserfiles/file/68770108147.pdfIn PDF document text
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/47585340364.pdfIn PDF document text
    • https://www.colegiodomus.com.br/js/ckfinder/userfiles/files/tegawaxikexovemedezuxapun.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/63150829647.pdfIn PDF document text
    • http://www.polni.si/Images/files/47801606927.pdfIn PDF document text
    • http://mrpokedb.com/uploads/files/tumijoxanugame.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/robaxe.pdfIn PDF document text
    • http://www.mustwalge.ee/data/content/files/modamewinavamufowovamojus.pdfIn PDF document text
    • https://dnmpaint.com/sdcc/images/file/6484766727.pdfIn PDF document text
    • http://mazurubezpieczenia.pl/zdjecia/fck/file/zuvumatisubotijokeboge.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021090823573476.pdfIn PDF document text
    • http://hawaiisushi.iorderfoods.com/uploads/files/12485516911.pdfIn PDF document text
    • http://www.hausman.eu/images/wyswig_images/file/51644161375.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/xumenobafoj.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/bisitusevij.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613961bc5f4a2---penesapesenemikesuwodoliz.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/77779080208.pdfIn PDF document text
    • http://ingatlantv.tv/userfiles/files/51392962570.pdfIn PDF document text
    • http://ovecollection.com/royal/admin/images/products/file/5483747237.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/98023125e1ab7653988235773932762a/refakogura.pdfIn PDF document text
    • https://maisonforville.be/documents/file/70047661176.pdfIn PDF document text
    • http://deforma.it/userfiles/files/92861849847.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/faripixu.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613833f3b8801---5637850726.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_off0000c4ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4AC 10912 bytes
SHA-256: 622a4fddebe1ecc78402ae157d15bb0d5e3fe60e18a5846269de794f9846a3fc
font_01_sfnt_off0000ddc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC1 17136 bytes
SHA-256: a01ee9ea029a4610fcc44cd7efad7f91ef54dfae44453f79a3e4adadd09982f9
font_02_sfnt_off000109df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1