Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1af4f6687583be8…

MALICIOUS

PDF

68.5 KB Created: 2021-09-26 14:47:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f1e9e085aa44b8e931c5e381143365a3 SHA-1: 3e888c0387a56f006c9d23e1337ac37c74ec0fd5 SHA-256: c1af4f6687583be84f84ead0e1d523d155006346512a6804457a66557bcc9519
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to PDF files on disposable or unknown domains, suggests a link farm designed to redirect users. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating a tactic to obscure the true destination and potentially distribute malware or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://newtop-eg.com/userfiles/file/guzeti.pdf In PDF document text
    • https://egokituz.eus/files/galeria/files/56264838499.pdfIn PDF document text
    • http://dywin.com/uploadfile/files/wafubemumiwemibuditeni.pdfIn PDF document text
    • http://meta-min.com/files/tedaw.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-9-8/20210908191449991996.pdfIn PDF document text
    • http://enkepharma.com/upload/files/651043586.pdfIn PDF document text
    • http://consorzio-csa.it/userfiles/files/sofumanebajaguvivakid.pdfIn PDF document text
    • https://italvaping.com/file/63647963805.pdfIn PDF document text
    • http://ominocoibaffi.it/userfiles/files/fadebobulexededigov.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/21912463558.pdfIn PDF document text
    • https://nomortiga.com/contents/files/navalalapimilepaxijegu.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/20925450672.pdfIn PDF document text
    • http://luligang.com/ckfinder/userfiles/files/74886445899.pdfIn PDF document text
    • http://sutipatika.hu/userfiles/files/feratexosefuredivuxum.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161445b16570cb---13150521490.pdfIn PDF document text
    • http://dc-8aaac82755d3.breakthroughwell.com/userfiles/files/pojitagelupibalomaninek.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/temes.pdfIn PDF document text
    • https://luxm.pl/userfiles/file/fozabixike.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca198e3570---61900329890.pdfIn PDF document text
    • https://medarbindia.org/ckfinder/userfiles/files/zegijaniderolezumiki.pdfIn PDF document text
    • https://www.seblocation.com/ckfinder/userfiles/files/54012942600.pdfIn PDF document text
    • http://domexpo.ru/up/file/4718574615.pdfIn PDF document text
    • https://dafelia.com/files/38549857112.pdfIn PDF document text
    • http://jjkxmy.com/upload/files/202109100733189910.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=one+piece+anime+download+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_off0000ae4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE4B 10512 bytes
SHA-256: 8b77e810521383f70b2f129eb3b8f6e41383e717c483fce05ad0d4aa02ac0a42
font_01_sfnt_off0000c638.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC638 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000de4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4A 14612 bytes
SHA-256: 85241f4d67632fa2d345897072cb22dc91e9fffd2bff1786c7d9522b60df996d