Malicious PDF — malware analysis report

Static analysis result for SHA-256 b385fa3a1270925e…

MALICIOUS

PDF

72.4 KB Created: 2021-07-09 12:21:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 95d5d38db7e2dcdd61bde3e61e3058b1 SHA-1: d0b29745b86edaa81e969d9d7a3d68ea02d93f98 SHA-256: b385fa3a1270925e215f41737725ea3a77444db162503b07650e0e39eb5594d3
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS upload directories and disposable hosting. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a39ddd7ad7c---62190818097.pdf In PDF document text
    • http://axiomestates.com/userfiles/file/21903510978.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/fuladiji.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/e92367c3584792c85016d36dd7f3794c/kugeledilonakapu.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7cf3b52808---12574079277.pdfIn PDF document text
    • http://truthtube.com/UserFiles/file/mefoferola.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/rebaxose.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160926d820fd9b---fizetotasigetubetefexot.pdfIn PDF document text
    • http://exclusivelimoservice.com/ckfinder/userfiles/files/kilelumibodowelodorapu.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba9cee029bb---tavoliluvijaluvanufatom.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/205dc8b17d96cb57ff298649b7c93abf/68828135485.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e215cd58868---57200608647.pdfIn PDF document text
    • http://hoacanh.net/luutru/files/fopebasufibofibabawev.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/dofenivavapipowejirikivo.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160756f3465335---48279448261.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/ndc6hft6dbjgjjm8v4frt8eaeh/mukivotefefogofozunim.pdfIn PDF document text
    • https://flyfinz.com/userfiles/files/67745765447.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/031451142760.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084364587366---molezimimi.pdfIn PDF document text
    • https://h1t-urlaurora1-turbo.com/contents//files/nedifuzukelela.pdfIn PDF document text
    • https://ibeguiristain.com/userfiles/files/sigulawaxarapewomoxe.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/62f207559a34905f15c68e18df471616/mixiguvowijexasonekiperub.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b3b0374fa8c---90427091901.pdfIn PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1e95292f1---tanelipesek.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160735ae8eb371---zogufanifigesi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=to+face+up+meaningPDF 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_off0000ba7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA7A 16308 bytes
SHA-256: 0a42909eee690ef2d9c4aa4ecb4272c774e2b50bf2d92db403a0a45558acb501
font_01_sfnt_off0000e4b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fccc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCCC 10476 bytes
SHA-256: ea60dafc12b00f18d272d6a68dcbbbd3a82208a1b121086ad9c5a58a3d0dc265