Malicious PDF — malware analysis report

Static analysis result for SHA-256 af960875de152f5f…

MALICIOUS

PDF

70.3 KB Created: 2021-09-17 17:36:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ac2b31bf87e6aba06bb223ff7d3ada1c SHA-1: 68fe99bcc23820fa26a57fd67605f7441c2fc459 SHA-256: af960875de152f5fb3429f9659aab167b6bd9bb827aa42e078e5cfc44d643ca7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised websites or disposable hosting, suggesting a link farm or phishing lure. The PDF structure and embedded content are consistent with attempts to redirect users to malicious sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://synerhu.ru/uplcv?utm_term=bridge+constructor+apk+mod PDF link annotation
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/zilojazuvekorumelapos.pdfIn PDF document text
    • https://georeno.ca/userfiles/files/41532913204.pdfIn PDF document text
    • http://lmleadmanagement.com/userfiles/files/80111295118.pdfIn PDF document text
    • https://dmshospital.com/mm_engg/files/53094566501.pdfIn PDF document text
    • http://88cpap.com/userfiles/files/14721357267.pdfIn PDF document text
    • http://flirdining.com/uploads/files/89554853860.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6b0fbee45---miwotipovo.pdfIn PDF document text
    • http://inarchengineering.it/userfiles/files/60965354001.pdfIn PDF document text
    • https://dagvandearchitectuur.be/_files/file/nolijorufo.pdfIn PDF document text
    • https://pasarantogel2.com/contents/files/jovegunufomibo.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614401d968419---88647224193.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/kawuvudujuvulebogebudirip.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/f2928de126413052863c0691410c0039/21453687005.pdfIn PDF document text
    • http://haenuri.net/ckupload/files/96331889934.pdfIn PDF document text
    • https://yuktogel.com/contents/files/61985908675.pdfIn PDF document text
    • http://npi-management.com/ressource/site-image/files/xikinotobapekajodigedu.pdfIn PDF document text
    • https://qfse.co/images/uploaded_files/ckfinder/files/1631223879_b50ff0601e.pdfIn PDF document text
    • http://morakothotel.com/file_media/file_image/file/49654396712.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/bivijuvugifuxiju.pdfIn PDF document text
    • http://hoteldanang.com/uploads/images/files/rebaxiwasexegolejopoduwip.pdfIn PDF document text
    • http://tweedehandswikkelaar.nl/app/webroot/files/userfiles/files/kokog.pdfIn PDF document text
    • http://randygordonlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/65639409350.pdfIn PDF document text
    • http://fiorenzuolatrack.it/userfiles/files/xiduzowigabajek.pdfIn PDF document text
    • https://drjou-vc.com/upload/files/4610086920.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614202d50df97---91557464999.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_off0000b431.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB431 14992 bytes
SHA-256: 31663028a6efcc6df58a1864cb4cc8ce18760be94c1493a0ccef02de8cb5bd34
font_01_sfnt_off0000da1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1A 11056 bytes
SHA-256: 28204dbe1563f80148083e9287bc34c416b959767b1cb5e765188a47ce276498
font_02_sfnt_off0000f3af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1