Malicious PDF — malware analysis report

Static analysis result for SHA-256 aeafb1b82a2ef0fa…

MALICIOUS

PDF

81.7 KB Created: 2021-09-24 07:16:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bc6844129c792fbc7d86bc31d9029cf3 SHA-1: 5917c0186b38ef575c19b157091eb45110b52d55 SHA-256: aeafb1b82a2ef0fabcd81fb8369dd64ceafafc154ff02d9df65b6776bb56f93c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to multiple external URLs, many hosted on compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://kunmobile.vn/files/uploaded/20210903/file/16521268538.pdf In PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/dufuvotokajefudakeribo.pdfIn PDF document text
    • https://netcsemege.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/xazebadotajo.pdfIn PDF document text
    • https://triatlonshop.cz/userfiles/file/25454718350.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/56973820615.pdfIn PDF document text
    • http://artstudiodesign.it/userfiles/files/tivofonijati.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/zelanup.pdfIn PDF document text
    • http://star-transform-moscow.ru/uimg/files/nimowowo.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e68b2c05c4---58145073337.pdfIn PDF document text
    • http://levne-pohary.cz/UserFiles/File/butasekaxesezazojuna.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/3d81f33961d2e46e0f9521cf6b761516/defunujulufemogepaz.pdfIn PDF document text
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109240801565680.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/71078638636.pdfIn PDF document text
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/wagogomupumamafelapadofo.pdfIn PDF document text
    • https://dhins.com/testingsites/advantage_aviation/assets/media/file/leruxitezi.pdfIn PDF document text
    • https://data-face.noithattoantam.vn/userfiles/file/91241212164.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/17296011506.pdfIn PDF document text
    • http://www.sudeshnamaulik.com/fckimages/file/30343941009.pdfIn PDF document text
    • https://ihotel2b.com/upfiles/editor/files/buzurowedekofakaxi.pdfIn PDF document text
    • https://proia.bg/userfiles/file/68850772695.pdfIn PDF document text
    • https://nyirfa.hu/uploads/files/pusaresabawevoxaliz.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/8f961285335c6ed7b56024c4f7bc6be5/49755237663.pdfIn PDF document text
    • http://lubrifianti-auto.ro/files/file/zekuko.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=friends+free+watchingPDF 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_off0000d842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD842 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f059.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF059 10652 bytes
SHA-256: cd4b1dfca511c7aa37cd87470b007ba7fb74c4bfafeceacd4d45bb15080c6994
font_02_sfnt_off00010886.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10886 18916 bytes
SHA-256: e3df62206c8b0362216762dee5c6a8fb9b7e6a8c488f893d730c491b9569ec31