Malicious PDF — malware analysis report

Static analysis result for SHA-256 6efc6341f7c50d37…

MALICIOUS

PDF

70.7 KB Created: 2021-09-15 14:08:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 56bcfa2aeb30f704582353c36f70a5f9 SHA-1: b9488c13da348a2268941116ce322f5baa0ef80c SHA-256: 6efc6341f7c50d37ac7e292dbe0a012ff504c96352a90b7a7a2008095f047cb7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting and are structured as a link farm, a common tactic for phishing or malware distribution. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to facilitate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://52fotki.ru/ckfinder/userfiles/files/96049593343.pdf In PDF document text
    • http://first-group.kr/ckupload/files/jamedowafepibobajikeguta.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/kuzameke.pdfIn PDF document text
    • https://vishalahospitality.com/ckfinder/userfiles/files/87242354864.pdfIn PDF document text
    • http://bajcsidavidfoto.com/_user/file/21650804278.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/zeroxulukunixaxisel.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1613e0785ded81---69712220003.pdfIn PDF document text
    • http://a2kat.ru/userfiles/file/mikusinutogavix.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/81508970593.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139cc0f2b6e9---tivarakije.pdfIn PDF document text
    • http://medianet2000.net/amm_prod/image_news_popup/file/42895084801.pdfIn PDF document text
    • https://menokatea.in/ckfinder/userfiles/files/zudazitez.pdfIn PDF document text
    • https://codecs.ro/images/file/14286992281.pdfIn PDF document text
    • http://nguyenphat.com/public/default/ckeditor/files/xutinegofavazam.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202109061242154834.pdfIn PDF document text
    • https://cpsguffanti.it/uploads/file/2504049004.pdfIn PDF document text
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/buwoja.pdfIn PDF document text
    • http://polletnv.be/uploads/files/guliwemobavabilej.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/sajibexewufof.pdfIn PDF document text
    • https://ctcitsupport.com/media/files/fezogi.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/jesadu.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a2bd2a88b5---60810947505.pdfIn PDF document text
    • http://jinyezi.cn/upload/tevovodajipotipozijosabow.pdfIn PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/35937082900.pdfIn PDF document text
    • http://abwcockeysville.com/uploads/files/zoputox.pdfIn PDF document text
    • http://rund-sro.cz/UserFiles/File/widedusudifirojumege.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=great+apps+for+android+wearPDF link annotation
    • https://b2cdemo.tickets.com/content/files/63339773936.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_off0000b7af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7AF 10568 bytes
SHA-256: 849336a17cf7e5f7e81f227654d58940226562b16241805e870997fe179be027
font_01_sfnt_off0000d002.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD002 14812 bytes
SHA-256: 0cdf36a2fcc8ac7b9a3d4f4711774c5b51b3fd0d2481ff37af2fe964209cd030
font_02_sfnt_off0000f534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF534 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1