Malicious PDF — malware analysis report

Static analysis result for SHA-256 6dc23e7d4b44b559…

MALICIOUS

PDF

81.0 KB Created: 2021-09-11 23:56:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0dbb97560fc24e0e8a7e29a90ca49a5d SHA-1: e4029333effb27b098aa6752b5aec24b635dbe11 SHA-256: 6dc23e7d4b44b5599067ff633c782c2247708189b5e5a4c95583dcd610344c3d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to suspicious domains and are flagged as part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • 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.
  • 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://gimnazjum-krasiczyn.pl/img/userfiles/file/mexolawusozotapa.pdf In PDF document text
    • https://dzido.pl/userfiles/file/zelelafapujupinu.pdfIn PDF document text
    • https://olamare.com/img/uploaded/file/bilorisit.pdfIn PDF document text
    • http://carmakers.cz/userfiles/files/mowaza.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/72967543790.pdfIn PDF document text
    • https://wegofa.com/userfiles/file/27606307535.pdfIn PDF document text
    • https://valeaflorilor.ro/img/uploads/file/malipekoxos.pdfIn PDF document text
    • https://dildendilecevirievi.com/upload/ckfinder/files/31471761332.pdfIn PDF document text
    • http://daoltrading.com/userData/board/file/xoluxoloruxabo.pdfIn PDF document text
    • http://hocikto.info/userfiles/file/wowoxevazipavufiri.pdfIn PDF document text
    • https://jin-hung.com/userfiles/file/24110217546.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/norob.pdfIn PDF document text
    • http://medwin.kr/userData/board/file/33134937350.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202109120003594544.pdfIn PDF document text
    • https://implantsdentairesdesmoulins.com/upload/editor/file/saburevidetirixi.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/46518396733.pdfIn PDF document text
    • https://towa-aaa.jp/userfiles/file/memegovasogadu.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/files/81451080499.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/zoredoxujobe.pdfIn PDF document text
    • https://jin-ji.com/upload/files/58401862489.pdfIn PDF document text
    • http://jogagongu.pl/userfiles/file/nabuzobajoguvilinujomeme.pdfIn PDF document text
    • http://hankyunget.net/userData/board/file/87347934685.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.excore.hu/ckfinder/userfiles/files/ruwapemenasimo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=tubidy+ios+download+mp3+mp4PDF 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_off0000d74e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74E 18028 bytes
SHA-256: d0f84eca73bf6105e6eb91a4019113cc5246b01bff3a493806455fcf1819690a
font_01_sfnt_off000105a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DBD 10876 bytes
SHA-256: 9dc51f379f84da06394cf36107cc3bf6ba354894f01079932a218d72471d5373