Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c409b38444781bc…

MALICIOUS

PDF

84.3 KB Created: 2021-09-22 14:28:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 383636d0d6288d36c774e7698c91c439 SHA-1: a2fd24ab30eb89c7fafe24d6ffb2cd698fb19e75 SHA-256: 7c409b38444781bcc321936d81c44f8e5179ae6ae9e1aba3e1855a52c40dc90e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs and is identified as a link farm, suggesting it's designed to redirect users to potentially harmful websites. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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.
  • 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://www.premiumtrade.ro/ckfinder/userfiles/files/lanab.pdf In PDF document text
    • http://poongdung.com/FileData/ckfinder/files/20210908_7F3ED4044A2DA28F.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/38305942582.pdfIn PDF document text
    • http://theclubburger.com/uploads/files/rezazoduwawegezikozof.pdfIn PDF document text
    • https://stalbeckers.nl/userfiles/image/file/namob.pdfIn PDF document text
    • http://robotsuk.com/luckingbros.co.uk/userfiles/files/mewapuveguzuzuwufuwid.pdfIn PDF document text
    • https://braindevelopmentmaps-org.neurondevelopment.org/userfiles/files/vonisofoxopat.pdfIn PDF document text
    • http://gyn-ordi.at/myPix/file/wudax.pdfIn PDF document text
    • http://assytekservizi.com/userfiles/files/52555118995.pdfIn PDF document text
    • http://jyy.jp/ckfinder/userfiles/files/20210921_150639.pdfIn PDF document text
    • https://chanty.dacola.com/upload/files/7887132008.pdfIn PDF document text
    • http://shop-cartuning.pl/userfiles/file/vofoxitipipumajasovu.pdfIn PDF document text
    • https://lmetinternationalschool.in/ckeditor/ckfinder/userfiles/files/veluzugatojis.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16140ab5b69f28---fokozuragifosaraxow.pdfIn PDF document text
    • https://ximangcampha.vn/upload/files/70983492465.pdfIn PDF document text
    • http://vertracapital.com/uploads/files/8088627574.pdfIn PDF document text
    • http://inkjetartandimage.com/Uploads/file/bijiwiduvunixenube.pdfIn PDF document text
    • https://aiwatopup.com/ckfinder/userfiles/files/47850062721.pdfIn PDF document text
    • https://www.twibiotech.com/plugin/ce1/ckfinder/userfiles/files/joleluv.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/26036678678.pdfIn PDF document text
    • http://naszemotyle.natura2000.pl/imgturysta/files/zudejifozejaluk.pdfIn PDF document text
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/figake.pdfIn PDF document text
    • http://www.huescalamagiaenfotos.com/userfiles/files/39966936502.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=torque+pro+paid+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_off0000de1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE1C 10268 bytes
SHA-256: b5730b55982dab8c43276e1f1c82a1de173c0dea02fb80120556fdb2a1a8a377
font_01_sfnt_off0000f50c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50C 21312 bytes
SHA-256: 59fd7a3bf3b8e11f64e22b03cf4a9746e39355e9f2c3d7a1c6e745c0e59d87f4
font_02_sfnt_off00012beb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1