Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a61de8ac0b633c2…

MALICIOUS

PDF

76.5 KB Created: 2021-10-05 01:43:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5aa9cea6a8b0696e1917645c81f7febf SHA-1: 26a8f33b8e6be9a9bae6c76cc7fab594e77b14bb SHA-256: 2a61de8ac0b633c2fb74dba8cf0a1656b76a071653bb547db9b4ce04c2ef2c4a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external URIs and links to compromised CMS uploads, suggesting a phishing or malware distribution lure. The PDF structure and embedded links indicate it's part of a link farm designed to redirect users to potentially malicious content, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://synerhu.ru/uplcv?utm_term=consequences+of+poverty+pdf PDF link annotation
    • https://www.auto-ecole-acm.com/ckfinder/userfiles/files/jasuwib.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/6d9694d97313e3a9ec71958f67b9dc4e/42109005075.pdfIn PDF document text
    • http://mebelhotel.ru/images/news/file/pigazafuwezevutefiwo.pdfIn PDF document text
    • http://dainindo.com/Uploads/userfiles/files/koruzavutubum.pdfIn PDF document text
    • http://kramnyca.info/img/upload/editor/file/2022534538.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles/files/fusaf.pdfIn PDF document text
    • http://caytrong.vn/Images_upload/files/vebaronuvemogaz.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/16148561a1462d---73674407199.pdfIn PDF document text
    • http://evpltravel.com/xv_image/file/7090021233.pdfIn PDF document text
    • http://centromp.it/userfiles/files/fafufotato.pdfIn PDF document text
    • http://kayamedbursa.com/userfiles/file/wixaxifelomudowawuwuzew.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614b7ec39faef---kisogifisigezi.pdfIn PDF document text
    • https://kindeeyudee.com/ck_files/files/65255603014.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16158a9e811a2a---pilifakejapeduwa.pdfIn PDF document text
    • http://sportingclubalbinia.eu/userfiles/files/46643068791.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/97ff38651d8436a63363b17162f6f15e/sutoduxubufagawesenabimi.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/63933738416.pdfIn PDF document text
    • https://oklogistic.lv/upload/file/48438384610.pdfIn PDF document text
    • http://gyermekhaz.hu/Content/site_images/files/57772195508.pdfIn PDF document text
    • https://hantverkarenisandby.se/UserFiles/files/45637240276.pdfIn PDF document text
    • http://s-pack.kr/userfiles/file/20210902002820.pdfIn PDF document text
    • http://wadsoda.com/UserFiles/File/27901086266.pdfIn PDF document text
    • https://biomedchita.ru/imeg_master/file/sidoluxitatiji.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/82207126357.pdfIn PDF document text
    • https://loffoxfitness.mvwebsolution.com/userfiles/files/nivusofevaguvenibo.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_off0000c862.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC862 16780 bytes
SHA-256: 1af5791f20c121276c5c0f47fb6c79562de6d030125bbcff7b7641c2ab8ff511
font_01_sfnt_off0000f391.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF391 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BA8 10768 bytes
SHA-256: 394c4d1470104061e8a4b8d8c9a4355963c16e5b963305e19f892dea956e3368