Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ce4df8bdd4c53ce…

MALICIOUS

PDF

83.6 KB Created: 2021-09-09 02:56:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 222586f7675bcb91cf1e44c83e2fb0db SHA-1: 1395c78df23978e152c2771fcc9135403fc8a499 SHA-256: 3ce4df8bdd4c53ce0323bbf007d9c99034f609cc2c61de4a0195125cb4bd4151
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high-risk heuristic firing for a random URL link, indicating malicious intent. The ML classifier and ClamAV detection strongly support this assessment. The embedded JavaScript likely attempts to download and execute a second-stage payload from the linked URL, which is a common technique for malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://nevjegyzek.eu/uploads/file/pasopo.pdf In PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/bivhjsgv7f92kk9kth5710gjv7/28841768183.pdfIn PDF document text
    • http://elliptical-trainers.ru/ckfinder/userfiles/files/regowiloza.pdfIn PDF document text
    • http://dentherapia.hu/files/file/14527374908.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/91342102448.pdfIn PDF document text
    • http://swapnakoodu.com/fck_uploads/file/67256419855.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/nebor.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/28646535952.pdfIn PDF document text
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/besojota.pdfIn PDF document text
    • http://www.como-grup.ro/fisiere/file/telizijerojiniweredeju.pdfIn PDF document text
    • http://kpdb.org/userfiles/files/1773646213.pdfIn PDF document text
    • http://gamjagolla.com/uploads/files/60566391387.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/jufupubimoseb.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b43f94f373c6955b3ac94cebd4757370/60192983402.pdfIn PDF document text
    • https://totspotdaynursery.co.uk/ckfinder/userfiles/files/38603689673.pdfIn PDF document text
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/61463136881.pdfIn PDF document text
    • https://chatsystem.site/js/ckfinder/userfiles/files/58171532493.pdfIn PDF document text
    • https://livermore.com/wysiwygfiles/file/94614388607.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202109/file/bewibi.pdfIn PDF document text
    • http://tevukasveza.lt/ckfinder/userfiles/files/daganituzimu.pdfIn PDF document text
    • https://sausalito.com/wysiwygfiles/file/97276392300.pdfIn PDF document text
    • https://napraforgohotel.hu/upload/file/16435169357.pdfIn PDF document text
    • https://www.piramideidiomas.com/ckfinder/userfiles/files/70559513808.pdfIn PDF document text
    • http://smepil.com/ckeditor/userfiles/files/luvifoxiwusiwi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=getting+more+pdfPDF 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_off0000e40b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE40B 10504 bytes
SHA-256: 43e067206f21d6cdbba8073745311239be3ebab2589d9f1053130638ff365de7
font_01_sfnt_off0000fba7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA7 17428 bytes
SHA-256: 456d0ae93f3ccda8b52c156be82d6f22ee5fc8e4015733310a711c4f4ac7f044
font_02_sfnt_off000128d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1