Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6f254ed9faa2749…

MALICIOUS

PDF

81.8 KB Created: 2021-09-19 04:37:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0a894e71a6cd597eed79083bf4934603 SHA-1: 73743c99784be64fbefaa0cae99d5df4f7a37243 SHA-256: b6f254ed9faa2749c50d141a29010ccada052b6b2912449139f8e46a915a04b7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which are structured as link farms. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of hosting many links on disposable domains, suggesting an attempt to distribute malicious content or phish for credentials. No scripts were extracted, but the overall structure and URL distribution point towards a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 https://infrive.ru/uplcv?utm_term=how+to+clear+data+of+app+in+android PDF link annotation
    • http://paolacaone.eu/userfiles/files/kibatabunumalujugir.pdfIn PDF document text
    • http://guidesdugrandlarge.fr/images/import/file/30491191176.pdfIn PDF document text
    • https://sanaspinler.com/calisma2/files/uploads/xofesosizulefuxemetadu.pdfIn PDF document text
    • http://reichspfarrer.sk/file/40678304604.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3d7785f7d---8703495024.pdfIn PDF document text
    • http://noithatphathuy.com/Images_upload/files/toneselazuvitifugarumofiv.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/rebonapidofixob.pdfIn PDF document text
    • http://www.bash.cl/media/file/63424994351.pdfIn PDF document text
    • http://pass38.com/images/contentimages/files/wodakixi.pdfIn PDF document text
    • http://bluecreator.biz/ckfinder/userfiles/files/fonomapojipege.pdfIn PDF document text
    • http://reckdance.pl/userfiles/file/sajejed.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/17725954147.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/nujakesodo.pdfIn PDF document text
    • https://xn----7sbbg1ddpkdc.xn--j1amh/uploads/files/wifedejitorin.pdfIn PDF document text
    • https://kham.vn/userfiles/file/muguda.pdfIn PDF document text
    • http://esangsok.com/upfile/files/regurapejijusoxerira.pdfIn PDF document text
    • http://pcccphucvinh.com/upload/files/mojukegovip.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613514868eb78---56981455636.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///78091480366.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1631751862.pdfIn PDF document text
    • https://558com.vegner.com/userfiles/files/20210918_030118.pdfIn PDF document text
    • http://ybshajiang.com/userfiles/file/2021-09-19/210919002512435868s11v2t70romj.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/kumarowedokugupodojenosu.pdfIn PDF document text
    • http://falcon.dk/sites/default/files/webfm/47111557438.pdfIn PDF document text
    • 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_off0000dcd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD6 17116 bytes
SHA-256: 1bfe32471687c08377797fac5c69290f32ed4beff3b70cef2bfc1f5632dd27cb
font_01_sfnt_off00010918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10918 10524 bytes
SHA-256: 9f08a79793be08ae994fd363a8ab7f7fa2459f449a631ab8a166d225f0e255ed
font_02_sfnt_off00012128.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12128 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1