Malicious PDF — malware analysis report

Static analysis result for SHA-256 c101a41d6ae1ab25…

MALICIOUS

PDF

80.4 KB Created: 2021-09-18 23:25:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 246b9091aa0435d1d99a5d3b020525b2 SHA-1: 775863031f03ce18fb899e4c358e262a299ade1b SHA-256: c101a41d6ae1ab25f9ce84e48cd825cc0f305902bdb389bced83c00beb73740d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be part of a link farm hosted on disposable or compromised domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6200

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://nomylo.ru/uplcv?utm_term=a+course+in+cosmic+consciousness+pdf PDF link annotation
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/ginikibafet.pdfIn PDF document text
    • http://avon-bratislava.sk/files/files/liwoxekalu.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202109061952004289.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/b30e2ef2804d9b7b24c569673ba76060/kidumovobazofeti.pdfIn PDF document text
    • http://artospace.com/pics/file/81298656518.pdfIn PDF document text
    • http://sushiyaslo.com/uploads/files/50107567200.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///55809080971.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/58839216673.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/kelutasefozasiguzupab.pdfIn PDF document text
    • https://alev.az/userfiles/file/82119446969.pdfIn PDF document text
    • https://ap-qatar.com/userfiles/files/baxomefovegofelijixos.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/161328baeb7879---6460692139.pdfIn PDF document text
    • https://malmospelmanslag.se/userfiles/file/lijonudotek.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210905_203149.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cecd7530f0---36510928386.pdfIn PDF document text
    • http://pastadimatteo.com/ckfinder/userfiles/files/41070253447.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/7478b4abe8ef1ff8f7df53069ccca5fc/42890371568.pdfIn PDF document text
    • http://solar-makernavi.com/ckfinder/userfiles/files/81234908533.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/60548237001.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/cf874e8855baea28d79a15231fd9ee58/75078188.pdfIn PDF document text
    • http://baheth24aqari.com/ckfinder/userfiles/files/xugifozopajozat.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/75497109475.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/fumimurageg.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/8a43648c78ca62e45beb3f2e1707dc6c/71701226379.pdfIn 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_off0000e138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE138 10556 bytes
SHA-256: f662f37cb68eba02d4bbc24502f78ed866af97c6fed906f3e73ef3cb4762f467
font_01_sfnt_off0000f93f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF93F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011151.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11151 18312 bytes
SHA-256: 4b34657a1d7c5af3a6e8a42a4fbe0f612a510881ae3c73eacadaf78f9aeea16f