Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff05fe993134ac87…

MALICIOUS

PDF

77.6 KB Created: 2021-09-03 00:57:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 575dba1b2d2cb9b005e0eed433e3ead9 SHA-1: be9c70f03f7417842c5d737ab83f2e165fe4b6c5 SHA-256: ff05fe993134ac877980346cde59733b7802a841a9a2937e15f26ff56af82910
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6343

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://inwebjor.ru/uplcv?utm_term=ielts+reading+test+pdf+file PDF link annotation
    • https://shop-ecobati.com/medias/upload/files/kiniwolajesazugilowuvom.pdfIn PDF document text
    • http://clarkhigh72.com/clients/3/34/34275c7d49a174b5f6cf03bf5966da6c/File/vufiwugiritogakozijov.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e416916f894---51155572375.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf021745a16---56766613921.pdfIn PDF document text
    • https://digireg.gr/upload/41126860693.pdfIn PDF document text
    • http://boracayg.com/FileData/ckfinder/files/20210807_8B9C5CE158EE90B0.pdfIn PDF document text
    • http://qianlong99.org/ckfinder/userfiles/files/1551923036.pdfIn PDF document text
    • http://xn--72c7caerxx0d3a9eve.com/UserFiles/File/gepisapateje.pdfIn PDF document text
    • http://csc-021.com/userfiles/file/20210728162135_xa20ld.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093fb9e51799---96106485876.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608cf142f2875---dapixironinovisofer.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/73486037070.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/b6fdbb7a1a4afe9024e3430efd3b3f2b/jasaxag.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c43f83554a2---94193434688.pdfIn PDF document text
    • http://4rrecycle.com/files/file/foxam.pdfIn PDF document text
    • http://portamarioarchitetto.eu/userfiles/files/50436336377.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c9ebb493b---gumojemepipoj.pdfIn PDF document text
    • http://kirsanov-maslo.ru/uploads/fesosilis.pdfIn PDF document text
    • https://svltv.in/userfiles/files/51609783191.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/56fd1ccd84560da5769282a136dcad39/govivizavixufejakof.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a8407e05456---xavepufe.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/t1d31io7lmcg9hr18385psddpk/dumegexivutoredijawidopa.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abead4ccaf4---15105340031.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_off0000d8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C5 10504 bytes
SHA-256: c7375376dda930e6801c0b3174f78fd4185ead937bb67fb6146d6247e570989f
font_01_sfnt_off0000f08a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001089c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1089C 17284 bytes
SHA-256: bdb0ce7d2a00dc3d292a737d60b8ee8adfc681911c505bba3dc3b2b786ddc4b3