Malicious PDF — malware analysis report

Static analysis result for SHA-256 cec3653457634e75…

MALICIOUS

PDF

80.1 KB Created: 2021-09-11 18:55:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c42f968ef7af680fcf8250f8ca178567 SHA-1: ec09b3c969356c65308e4ffdf464298c163551cd SHA-256: cec3653457634e75eeccf66c9624d6c6386cc13479e212780aa3be2c7779f742
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 PDF files on unknown domains, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection to these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://karlschool.org/uploads/files/202109082036097888.pdf In PDF document text
    • https://sofupingame.com/calisma2/files/uploads/gajimozitaxupavupes.pdfIn PDF document text
    • http://olynskiconstruction.com/pics/file/88453675232.pdfIn PDF document text
    • https://heart-calligraphy.com/uploads/files/202109011727351346.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/72023454302.pdfIn PDF document text
    • https://reformedgeneration.com/userfiles/file/wadij.pdfIn PDF document text
    • http://sd-admin.fazendapenaazul.com/ckeditor/uploads/files/98894269167.pdfIn PDF document text
    • http://plusk-car.com/js/upload/files/86747735277.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/21942231788.pdfIn PDF document text
    • https://riondene.ch/img/uploads/file/mabulenamuvomob.pdfIn PDF document text
    • https://peisheng.org/uploads/ckfiles/files/613c719b3447b.pdfIn PDF document text
    • http://24x7taazasamachar.com/assets/ckfinder/core/connector/php/uploads/files/vejuzik.pdfIn PDF document text
    • https://predial-rua-nova.pt/056-CovadaLua/images-editor/file/31061687657.pdfIn PDF document text
    • http://huucodatlanh.com/userfiles/file/20598547806.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/65931173815.pdfIn PDF document text
    • http://travelport.pl/userfiles/file/xolewewo.pdfIn PDF document text
    • https://10playsolutions.com/clients/softklk/documents/_articles_/file/58300472326.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/24822356261.pdfIn PDF document text
    • https://orig-shop-gsm.ro/ckfinder/userfiles/files/motegoviporu.pdfIn PDF document text
    • http://unite-chem.cn/upload/files/goporosivuxisogapawo.pdfIn PDF document text
    • http://cuathepvangohaiduong.com/images/ckeditor/files/wejizuresod.pdfIn PDF document text
    • https://trickapotisk.cz/webpagebuilder/ckfinder/userfiles/files/44760128670.pdfIn PDF document text
    • https://www.benkorner.nl/admin/library/ckfinder/userfiles/files/rijixajeduxex.pdfIn PDF document text
    • https://mygrind.ie/userfiles/file/mupidemas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=watch+the+abcs+of+death+online+freePDF 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_off0000cfd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFD6 10704 bytes
SHA-256: 96bc219f1cc22278daa0e4451cdf840ddb0c1b77531065cd7d1dff2b4deaec75
font_01_sfnt_off0000e859.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE859 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001006b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1006B 19032 bytes
SHA-256: 835b433b0c4398e23d4a7685150af76bd0c836956a497a0ec66e892dbd3f4713