Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad365fd2d06e5353…

MALICIOUS

PDF

80.2 KB Created: 2021-09-14 01:15:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c520acb7cf120dc0e8196adae193050b SHA-1: c2a3f402101109993e48c89f25e56cb50c644a45 SHA-256: ad365fd2d06e535386937fa498758ccf6580ed796eb45de400bfe5b75f5360e9
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution attempt. The presence of embedded JavaScript indicates an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://medvor.ru/uplcv?utm_term=kotlin+bundle+example PDF link annotation
    • http://baominhlabors.com/upload/files/25107925732.pdfIn PDF document text
    • https://vantainoidia.vn/ci/userfiles/files/zulugezomuk.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/rifopiguluzujuredikiz.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/16623496234.pdfIn PDF document text
    • https://superiorservicesandsolutionsfl.com/nbloom/fckuploads/file/14879813455.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7dc5b4cbe---24587956288.pdfIn PDF document text
    • http://tnslib.su/userfiles/files/konodedesukijidi.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/gidolikifupavej.pdfIn PDF document text
    • https://anctools.com/ckfinder/userfiles/files/60655329190.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc00c8dea9---jukatewejaxuko.pdfIn PDF document text
    • http://fusen-es.info/yamituki-n/uploads/files/52046794183.pdfIn PDF document text
    • http://ukicda.com/admin/fckeditor_upfiles/file/2021090221491580554.pdfIn PDF document text
    • https://shunnasato.com/xegaruratigerib.pdfIn PDF document text
    • http://gzlmjx.com/data/home/bxu2343160066/htdocs/uploadfile/files/vibaweganarivaziw.pdfIn PDF document text
    • http://piannocreativo.com/js/new/fckeditor/userfiles/file/fezilez.pdfIn PDF document text
    • http://nanchang.chinatupai.com/web/js/ckfinder/userfiles/files/zamugelosenozibokupo.pdfIn PDF document text
    • http://defhjdr.friend-match.com/upload/files/tudafikera.pdfIn PDF document text
    • https://davidfoleyinc.com/userfiles/file/40982371193.pdfIn PDF document text
    • http://myphamvickwhitebeck.vn/luutru/files/kafanuvafojolujove.pdfIn PDF document text
    • http://talentfuturesservices.com/sharpinstitute/images/files/vituvufo.pdfIn PDF document text
    • http://rydelko.pl/userfiles/file/2303531759.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1613d44890e14f---nukefutokara.pdfIn PDF document text
    • http://celcg.pl/uploaded/file/sevusamisijovajuf.pdfIn PDF document text
    • https://www.newhorizonscrisiscenter.org/ckfinder/userfiles/files/46831150262.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_off0000d317.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD317 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB29 18092 bytes
SHA-256: 41e639bbdc49bfc4faec035e458f8053866747ea85b8b1e9390eb39fe1f41c55
font_02_sfnt_off00011ab7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB7 10620 bytes
SHA-256: febf66ff68508213b0d5901387e505e815822d4883109f53005719d5b8190624