Malicious PDF — malware analysis report

Static analysis result for SHA-256 64b870a4e2fa093f…

MALICIOUS

PDF

86.1 KB Created: 2021-09-03 23:24:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 542cdf7ea7fd6af8637a83276591c16c SHA-1: 761ab3480bdf5c5413a5808aec171284149352b3 SHA-256: 64b870a4e2fa093fa0baa01de9b2782b1e54aaf6f9e607db56120ede5b83004e
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple domains, including compromised WordPress sites and potentially disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of numerous external URIs and the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristic confirm the nature of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://thermogroup.ru/uploads/files/5645702999.pdf In PDF document text
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/a0b2f4dc30b7d4791241dcb9c528410d/26468652281.pdfIn PDF document text
    • https://okazionche.com/files/34163329938.pdfIn PDF document text
    • https://norservis.cz/files/files/xiloritonipafeto.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/81922449688.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/3v2bul5kklram1kcuccpkimvv1/nidetitere.pdfIn PDF document text
    • http://pettwayfamilyreunion.com/clients/39389/File/jupopenerevisixixe.pdfIn PDF document text
    • http://grupopiscis.com/upload/files/limugibof.pdfIn PDF document text
    • http://puppiesjust4u.com/clients/c/c8/c8a8d0e690f73854b1e7a5fbb9521f82/File/3954123843.pdfIn PDF document text
    • http://jeyadhurgatemple.com/userfiles/file/lugigapabagasosefovuvi.pdfIn PDF document text
    • http://www.gc-antey.ru/ckfinder/userfiles/files/kegogejororijo.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/24223203006.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/be1f678886baa76ce88fe7c9f37e404c/28875650318.pdfIn PDF document text
    • http://eminenceinc.com/userfiles/file/refivegusiputogafukixeba.pdfIn PDF document text
    • http://cmi.nfe.go.th/ckfinder/userfiles/files/lesomoxit.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/xisenisululotesafufos.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/donofulokumijufiradu.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/14934730488.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/88074202433.pdfIn PDF document text
    • http://vilocom.net/webroot/img/files/17949698722.pdfIn PDF document text
    • http://travelsi.ru/ckfinder/userfiles/files/73472362859.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6dce3925bd---6885219506.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=reading+comprehension+level+pdfPDF 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_off0000edb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB3 11080 bytes
SHA-256: fb0f9c65ea4eee15af7af53e76b51e26e1fed05c67abe072703b1704de0d278b
font_01_sfnt_off0001070c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1070C 17016 bytes
SHA-256: c2ab7e72dbee45bff58f57f6c64da73d2c9d9a701d566530dc924f5442fcc1ec
font_02_sfnt_off000132c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1