Malicious PDF — malware analysis report

Static analysis result for SHA-256 c97801c6249c6fd4…

MALICIOUS

PDF

71.1 KB Created: 2021-09-21 11:12:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6f41d2f5971493728df1716a8d621cc6 SHA-1: 371fa83860110fd913139d3ad3d1f0fe990dd9fb SHA-256: c97801c6249c6fd4ea331ceee3fd7eed380a1145a44b29a55cd4bc4ca3807736
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple PDF-specific heuristics related to URI and link farms reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 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 http://szerecsengyogyszertar.hu/editor_up/85517679352.pdf In PDF document text
    • http://bettaletroom.com/file_media/file_image/file/14704365426.pdfIn PDF document text
    • http://unsersohn.com/images/file/2781397184.pdfIn PDF document text
    • https://2b3la571ga-70p.com/contents/files/97481337081.pdfIn PDF document text
    • https://oancora.com/ckfinder/files/dowosol.pdfIn PDF document text
    • http://upsshop.ru/ckfinder/userfiles/files/lafuvibivopagivu.pdfIn PDF document text
    • http://onlinepravenconsultant.com/uploads/wysiwyg/files/87016497782.pdfIn PDF document text
    • http://gyarmatilovastorna.hu/userfiles/file/3827918337.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/56121353014.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/nadvre4cgfl2ilvg3770f721ka/mukosetixetumin.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/wolaxow.pdfIn PDF document text
    • http://quesnelfoundation.ca/userfiles/file/tuzujalavodozunogowitewer.pdfIn PDF document text
    • http://myphammonly.com/luutru/files/41424641293.pdfIn PDF document text
    • http://xenangheli.vn/public/files/xuwanifisoxibenoraxa.pdfIn PDF document text
    • http://caycanh.vn/images/fck/file/regifavewitivawusiwinef.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/bidofak.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16147e8e977849---fapan.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/8iq0g3smb1ko0mrmbe22nt760a/8080804457.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/42790551362.pdfIn PDF document text
    • http://cec-intl.ru/app/webroot/files/file/woxatebiw.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/mesowerenugap.pdfIn PDF document text
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/54137136206.pdfIn PDF document text
    • https://norservis.com/files/files/6750479621.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=xiaomi+poco+x4+release+datePDF 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_off0000b23f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB23F 16876 bytes
SHA-256: c935d0e256bb351de53aa701992ed5ca13280552136cf2372d05977b39364925
font_01_sfnt_off0000de34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE34 10756 bytes
SHA-256: 7f17cc37cd797fb3a92d32b59c7be7f6227587738cea3093782939867c976443
font_02_sfnt_off0000f705.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF705 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1