Malicious PDF — malware analysis report

Static analysis result for SHA-256 cecf90917cee7bbe…

MALICIOUS

PDF

83.1 KB Created: 2021-09-18 10:05:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 50681ded365db14967a9efe64561f77c SHA-1: 78f66afd52b9683619adea433b166fc0b8caddc9 SHA-256: cecf90917cee7bbee7f845fd642c193a4ba4c5a189dd0250b6dbb6d56abbba27
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to suspicious domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high likelihood of this document being part of a link farm, designed to manipulate search engine results or redirect users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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 http://104408017.linker.tw/files/detijokiragixulazadaw.pdf In PDF document text
    • https://lederstuehle-shop.de/ckfinder/userfiles/files/31428972562.pdfIn PDF document text
    • https://tattica.byespresso.com/app/webroot/files/upload/files/menopoxelowus.pdfIn PDF document text
    • https://isigakizima.net/img/tmp/file/gorumamusepolumim.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/76808915038.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/suretijetaxafa.pdfIn PDF document text
    • https://el-tall.pl/pics/file/67765997784.pdfIn PDF document text
    • http://hanyangsteel.com/files/fckeditor/file/2113034342613f6af97c7e3.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/63993135425.pdfIn PDF document text
    • https://west-holding.com/userfiles/file/7411581868.pdfIn PDF document text
    • http://www.leads-bd.org/app/webroot/js/ckfinder/userfiles/files/nepeburikuvazox.pdfIn PDF document text
    • http://bighost.vn/uploads/userfiles/file/4068044852.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///girukijuvetazepebaris.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/06121544522.pdfIn PDF document text
    • http://mstreatmentadvances.com/userfiles/files/21970886161.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/26712969364.pdfIn PDF document text
    • http://investbuild.ru/var/upload/file/fuxunifuzes.pdfIn PDF document text
    • http://rubella2.integra-sh.com/userfiles/file/juzokasidibejadoj.pdfIn PDF document text
    • http://slstudio.it/userfiles/files/65079600403.pdfIn PDF document text
    • https://anyimaker.com/upload/users/files/lexebore.pdfIn PDF document text
    • http://herve-coiffure.ci/files/wodupexesatulitokipimegod.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/71278a2900a870b917bab813e18a50c5/givusumakugawewogix.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/xuzokegadoge.pdfIn PDF document text
    • https://glaze-metalart.com/upload/files/dexejevezununazaxokedu.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140618029f1a---toxesamibuzatel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=pel+40+inch+led+price+in+pakistanPDF 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_off0000e201.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE201 10784 bytes
SHA-256: 1d74583d1040f0ffa3e46374f1016ae3a525e5504c53ccb52730d1769189e06c
font_01_sfnt_off0000fac6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAC6 16920 bytes
SHA-256: 40d192027a0ed043ee66147a24362cc87834b2be481ba8a7053cb3d14a54c6a6
font_02_sfnt_off0001262c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1262C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1