Malicious PDF — malware analysis report

Static analysis result for SHA-256 253fe864b1870d16…

MALICIOUS

PDF

82.4 KB Created: 2021-09-13 05:16:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 7e3181d4d14b2ff162e0d9045e8a6895 SHA-1: 413c0890e8c905575176666d6d490268c1238a81 SHA-256: 253fe864b1870d1663437329aaf84cfdc625c461c0ee68d4bb8473788f5ae50c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for exploiting vulnerabilities or redirecting users. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM and the numerous unknown URLs suggest a link farm or phishing campaign. ClamAV and ML classifiers confirm its malicious nature, likely as a phishing lure or a downloader for further stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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
  • 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 http://nzozkrowodrza.pl/uploads/editor/file/47776414259.pdf In PDF document text
    • https://rcot.org/userfiles/file/30747496674.pdfIn PDF document text
    • http://www.perchegouet.com/ckfinder/userfiles/files/xuwavujufaduk.pdfIn PDF document text
    • http://iccjsc.com/images/uploads/files/ladij.pdfIn PDF document text
    • http://kielcenoca.pl/files/file/15348329854.pdfIn PDF document text
    • https://nyig.com/files/file/33970990183.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/99454411993.pdfIn PDF document text
    • https://cytokin.ca/upload/editor/file/zogafozirefupigasewamuwa.pdfIn PDF document text
    • http://www.herbertvanderbrugghen.nl/draft/32181436095.pdfIn PDF document text
    • https://apoiotelecom.com/imagens/img_fckeditor/file/gunonimokudonubep.pdfIn PDF document text
    • http://quiltingacademy.com/fckeditor/userfiles/file/90693515935.pdfIn PDF document text
    • https://flammerouge.ch/userfiles/files/duwanoraxojuxuwobov.pdfIn PDF document text
    • https://stayinbranson.com/ckfinder/triplebuserfiles/file/36557843743.pdfIn PDF document text
    • http://burattinojatek.hu/userfiles/file/xiwerabawufudodeb.pdfIn PDF document text
    • http://www.puhito.hu/uploads/38841915065.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/70835381169.pdfIn PDF document text
    • http://sineadstone.com/userfiles/file/85951057569.pdfIn PDF document text
    • http://pekbdt.com/filespath/files/20210904032942.pdfIn PDF document text
    • http://cgpharma.in/cote_dor_import/admin/ckfinder/userfiles/files/20026297822.pdfIn PDF document text
    • http://trieuduong.com/images/Download/19072364850.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210910040154.pdfIn PDF document text
    • http://dpsszczytno.pl/photo/file/21360240836.pdfIn PDF document text
    • https://cpc-serbia.org/js/files/wekibavizejofi.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/9796137200.pdfIn PDF document text
    • http://eros-arena.com/eros/userfiles/file/79570999235.pdfIn PDF document text
    • http://cartopack.be/Images/file/nosum.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210912_210213.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=thoptv+online+websitePDF 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_off0000df37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF37 10340 bytes
SHA-256: a933b9e1d73387b56c407268faa28aaef25191ed80e59c3638bb82a6d2940881
font_01_sfnt_off0000f64e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF64E 17636 bytes
SHA-256: 62e945ef44a8ebdc32d62e33e63ac4a7fbf45bd5fcca8c8db75750a722ad95c1
font_02_sfnt_off000123d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1