Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d661d3cc5c386cd…

MALICIOUS

PDF

69.1 KB Created: 2021-05-09 21:12:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 035cf89bfa38e5a441fcefbd854a24a0 SHA-1: 562fe76baab69f487214d0458eb5b40419a1edce SHA-256: 8d661d3cc5c386cd9211db0b557259a08d20e62638533b4915b4c02ebb295403
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, and contains a large number of external links, many of which point to potentially malicious domains. The heuristic 'PDF_SEO_LINK_FARM' indicates a deliberate attempt to create a link farm, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF format can embed JavaScript, which could be used to facilitate redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kuzutuzo.ru/strik?utm_term=el+negocio+del+siglo+xxi+audiolibro
    • https://newogevalofa.weebly.com/uploads/1/3/4/8/134898908/biritepen.pdf
    • http://fullpisetc.ru/computer_launcher_pro_apk_2020u7tmn.pdf
    • https://vipeketiduwe.weebly.com/uploads/1/3/1/6/131636725/5036680.pdf
    • https://cdn-cms.f-static.net/uploads/4452618/normal_600dc252c6e8c.pdf
    • http://mainsale.pro/what_does_the_gold_santa_muerte_meanmmm2k.pdf
    • https://cdn.sqhk.co/wupofolizaj/XjbgcGW/59919978790.pdf
    • https://kofuremejekesor.weebly.com/uploads/1/3/4/2/134235353/5674497.pdf
    • https://kofijowuz.weebly.com/uploads/1/3/4/4/134446653/xusukekor-xebufumazi-wedujisimib-murole.pdf
    • http://gufutaca1.xyz/philips_respironics_system_one_bipap_auto_bi-flexu66r3.pdf
    • https://cdn.sqhk.co/fugolamudara/nhjjidZ/xujexo.pdf
    • https://cdn.sqhk.co/wixefawoz/icWVyih/59013632029.pdf
    • https://cdn.sqhk.co/pixazizaze/2evAgh4/17473612078.pdf
    • https://jafipununevov.weebly.com/uploads/1/3/0/8/130814040/xikologovekulajur.pdf
    • https://xafokakiza.weebly.com/uploads/1/3/2/7/132710638/6535a9712c.pdf
    • https://japapitamamevoj.weebly.com/uploads/1/3/2/7/132740309/149466.pdf
    • https://static.s123-cdn-static.com/uploads/4496170/normal_5ff146faf07f4.pdf
    • https://cdn.sqhk.co/zovitamojim/hWijaUK/pixel_rally_apk.pdf
    • https://pulijapejupexeb.weebly.com/uploads/1/3/4/0/134041872/1079246.pdf
    • https://wusikizojig.weebly.com/uploads/1/3/4/8/134883510/7dc2ae37.pdf
    • http://shoppermarket.online/is_the_epson_1430_discontinued1cbv4.pdf
    • https://cdn-cms.f-static.net/uploads/4452392/normal_6060f8b2f2116.pdf
    • https://cdn-cms.f-static.net/uploads/4420222/normal_603c2a3c79108.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/suxiweke/skype_interview_questions_and_answers_for_freshers.pdf
    • https://s3.amazonaws.com/pekatikisuruki/boethius_consolation_of_philosophy_book_1_shmoop.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ceac.bin
641c9e12a7b5f8d239a94ca02e27aee426129626f5862e973f408d118c8b7541
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEAC 5272 bytes
font_01_sfnt_off0000e0ac.bin
3a9e4e12d9ca5fa939663d461a0b0691b952dacad73dc7c267c36ef51ee597c6
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0AC 11344 bytes