Malicious PDF — malware analysis report

Static analysis result for SHA-256 f770cf639dccb429…

MALICIOUS

PDF

83.6 KB Created: 2021-09-07 13:23:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 7e0e32448abfa540ad703d5a3f3023f1 SHA-1: 929bea4c021ce8674a9032f43c9539b5301324fa SHA-256: f770cf639dccb4292a9a822788ea083d288a81a28e145947ce653c1ca5c0c904
156 Risk Score

Malware Insights

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

The PDF contains a large number of external URIs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting. This structure is indicative of a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://philabc.ru/uplcv?utm_term=business+statistics+mean+median+mode+pdf PDF link annotation
    • http://thewesternmist.com/userfiles/file/27069613563.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f00b4e86676---panurozowevatowuxo.pdfIn PDF document text
    • http://kesifveotesi.com/files/39986354447.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094dfe4d21d5---sidumuxigosigajarupi.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/37615738513.pdfIn PDF document text
    • http://karinameal.ru/imgdish/files/vitatimagalona.pdfIn PDF document text
    • https://campermagazine.tv/public/file/51055384464.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/nhgmshdrcgm5itser4rld6o2jo/80974562075.pdfIn PDF document text
    • http://abaj.cz/UserFiles/File/murur.pdfIn PDF document text
    • http://asclyziarskyklub.sk/userfiles/file/52467539890.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/31685932123.pdfIn PDF document text
    • http://harc-ias.vn/Images_upload/files/67476251701.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c307b417cdf---maniparitijazaj.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1610aa58e36bf4---77687101187.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/3b231cf59af249529bd9f1002d00f0c7/nevimologapifevalago.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/fgapt1cpa1lav3dtu4g5se96bv/75873114417.pdfIn PDF document text
    • http://okvin.org/userfiles/file/xasokufi.pdfIn PDF document text
    • http://asacnfservices.com/ckfinder/userfiles/files/26404532435.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/rirusuwidutafudo.pdfIn PDF document text
    • http://gzmzwl.com/Uploadfiles/files/52066495672.pdfIn PDF document text
    • https://webrekruit.com/php_codes/Scott/VieauAssociates/code/userfiles/file/regiburapututarisajek.pdfIn PDF document text
    • http://yuanyoujie.vip/userfiles/file/4246479921.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_off0000e0c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C0 10788 bytes
SHA-256: 8848989ab68f10bec526c93b2e9bb7ea3b860d0baeb6fa5a0d19b621f322c43b
font_01_sfnt_off0000f9a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000111b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111B5 17900 bytes
SHA-256: 6550a6c8deada861664df467913e8a412eecd28be682fafd5aaf38baa350b2f3