Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a4bd1689ac6f67d…

MALICIOUS

PDF

78.2 KB Created: 2021-09-15 21:19:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fad7e2d064fa67aa23483628ac455bff SHA-1: 52953e94fa5b97f98a5a09154acf1bca7248b261 SHA-256: 6a4bd1689ac6f67db92ea46d235440187585ccd33a2287b55c10364553d3d091
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://phutungtdc.com/upload/files/mutipibaxenul.pdf In PDF document text
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/32144775881.pdfIn PDF document text
    • https://classykitchen.pl/web/uploads/files/9159288963.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/atqdq7qa2kb2vuhc98c950ecbn/56264699912.pdfIn PDF document text
    • https://zweefvlieg.net/userfiles/file/wubevotudukusorevukixexe.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613c4ac8d51a4---dobuvewifuxarovesawo.pdfIn PDF document text
    • http://sarkar.ie/userfiles/file/79072252677.pdfIn PDF document text
    • http://nazycakes.com/userfiles/file/xanodanaxesavefozof.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/jabewozigozogazeku.pdfIn PDF document text
    • http://ylplj.com/ckfinder/userfiles/files/22466350863.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16132392214c25---9528603115.pdfIn PDF document text
    • http://www.w.radeton.cz/ckfinder/userfiles/files/bonopizesufapet.pdfIn PDF document text
    • https://rubenoferro.com/userfiles/file/pubenizagatudunukiju.pdfIn PDF document text
    • http://uran-berlin.com/userfiles/file/muved.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/1a4b82338c084c3e76d4385ef7627029/64730189454.pdfIn PDF document text
    • https://fajanav.com/aym_image/files/52287590369.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/5c37e997365459ea1de45fc71e5c9f8f/3803835724.pdfIn PDF document text
    • http://martom24.pl/martom/userfiles/file/masetino.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343dc7026fc---9559443887.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/31608809273.pdfIn PDF document text
    • http://change4best.ru/upload/file/rozexogadasomibimevixe.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/50450021039.pdfIn PDF document text
    • http://sprostredkovanieuverov.sk/res/file/49839683966.pdfIn PDF document text
    • http://myphammonly.com/luutru/files/95842751748.pdfIn PDF document text
    • https://nestsearch.in/admin/uploads/file/75693802005.pdfIn PDF document text
    • http://thesciencenetwork.org/uploads/files/wolelevotiforojikigadod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=watch+henry+danger+full+episodes+freePDF 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_off0000ce02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE02 11108 bytes
SHA-256: 910ab05888f81dc0e1ce0e14bde7f70cd7ecc9a9be23e9e5f3363f4aee3893b5
font_01_sfnt_off0000e7ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7AD 16524 bytes
SHA-256: fdf3cb32551ee8b4cf1e14c4de5720a607e77916ecb90675d2b75b560adf393c
font_02_sfnt_off0001129b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1