Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8970b40ea29faeb…

MALICIOUS

PDF

76.3 KB Created: 2021-09-18 17:36:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c8f0250237c89006b25add42b3be7483 SHA-1: 815e575205767c40d30ae6858a4604873db954e3 SHA-256: e8970b40ea29faebdd5e90e4d2368d229d9428dd84a466233b4848454484d4ac
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document flagged by multiple heuristics as malicious, including a high-severity PDF_RANDOM_URL_LINK and ML_NYX_PDF_MALICIOUS. It contains a large number of embedded URLs, many pointing to potentially disposable domains, suggesting a link farm or phishing lure. The ClamAV detection further supports its malicious nature, identifying it as Pdf.Phishing.Trojan. No scripts were extracted, but the overall structure and URL distribution indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • 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.
  • 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://kocavietnam.com/upload/files/zazeroxolugijijumamotitur.pdf In PDF document text
    • http://rund.cz/UserFiles/File/82626745648.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/files/situf.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202109052345484596.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/vitewijupimofevaro.pdfIn PDF document text
    • http://kechengchem.com/upload/files/mamep.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613637e3200dd---pakedazigoguvikiruxi.pdfIn PDF document text
    • https://jurvamartin.com/userfiles/file/wokodasalukasofijiga.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/wekamefupipemoxave.pdfIn PDF document text
    • http://katachizu.com/img/news/files/nofuzix.pdfIn PDF document text
    • https://xn--pssa17sw71b.tw/upimages/files/xorapixemer.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/tawev.pdfIn PDF document text
    • http://daisytalavera.com/userfiles/files/xuvilafamubugemubof.pdfIn PDF document text
    • http://dunakeszi.varosom.hu/userfiles/files/mizowupika.pdfIn PDF document text
    • https://hinodanang.com/uploads/image/files/mirebegeteda.pdfIn PDF document text
    • http://montpellier-businessplan.com/mbp/upload/images/images/upload/ckfinder/6087009119.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/sekununusamuza.pdfIn PDF document text
    • https://rusepress.com/uploads/wysiwyg/files/98560408935.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/65331193650.pdfIn PDF document text
    • https://guruvinodji.com/Userfiles/file/nusomifudo.pdfIn PDF document text
    • http://119pump.net/d/files/vofotanej.pdfIn PDF document text
    • http://justsayhi365.com/uploads/file/44620250194.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/76581144728.pdfIn PDF document text
    • http://ukrfirework.com/images/file/36863422469.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/ripadumomurofirekaji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=xiaomi+phone+apkPDF 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_off0000c89a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC89A 10204 bytes
SHA-256: 359e90ff334c8980f73fad39067c45b57348fcfaccb839f68de0b139632ed718
font_01_sfnt_off0000df39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f74b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74B 17060 bytes
SHA-256: 588a4b121a63f78c0197415b294f496f9fbaa55e44a7fcf106261566f95f5f67