Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a8ed32160b13c9…

MALICIOUS

PDF

81.3 KB Created: 2021-09-17 07:47:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4f4f13f887c264bc5ec30577e20b60c3 SHA-1: e9a0d2026312391c4096bf1de2dcc73d345b386b SHA-256: a5a8ed32160b13c9de4f0c32fc74f18aace7c202dbd6bfa4f874124d9ab18bd9
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to compromised websites, suggesting a phishing or malware distribution scheme. The PDF structure and link farm heuristics further support this, as they are common tactics for redirecting users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • 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 https://crysiq.ru/uplcv?utm_term=what+2+colors+make+purple+paint PDF link annotation
    • http://joesservicecenternj.com/userfiles/files/53097153286.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/l7cg9m0nvcb8uo0t4ff8snpqik/27107459766.pdfIn PDF document text
    • http://kbautotech.com/board/datafiles/imagefile/17727470726.pdfIn PDF document text
    • https://bnbcostaverde.it/userfiles/file/70662051500.pdfIn PDF document text
    • http://bippex.com/filespath/files/20210904030631.pdfIn PDF document text
    • https://valeaflorilor.ro/img/uploads/file/53457114759.pdfIn PDF document text
    • http://cmtl.in/uploads/userfiles/file/file/41445527455.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/161376cbe6c69e---nupimusobigijefivobawir.pdfIn PDF document text
    • http://sh-songshi.com/admin/upimg/file///39422620770.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/a75be310828b2059a0ccdeff32c3111f/95826809245.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/wopoxokawaxunesirof.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/12933552620.pdfIn PDF document text
    • http://goodlife88.com/uploads/files/6386430742.pdfIn PDF document text
    • http://xmzs.org/userfiles/file/gifadamizawuxeb.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/vagowivepovuwobisubi.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/60358648094.pdfIn PDF document text
    • https://skopjemuzikon.pmgrecordings.com/ckfinder/userfiles/files/47800881584.pdfIn PDF document text
    • https://rosenstein.lu/userfiles/files/92379706185.pdfIn PDF document text
    • http://achilleferolla.it/userfiles/files/16081730504.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/b9od639negebrs1q7bgpl58itf/97972875409.pdfIn PDF document text
    • https://comfort8889.com/upload/files/liloborejexesamovaxufi.pdfIn PDF document text
    • https://phm.vn/upload/files/wunerimekax.pdfIn PDF document text
    • 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_off0000d8c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C6 17824 bytes
SHA-256: 5c98fe95af1d43904a7f3830eae0a9954279b6b6b6becf2822b986c3738ed4d5
font_01_sfnt_off0001062e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1062E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E45 10944 bytes
SHA-256: 16b49f4289c2d408edd95b97a3fc91cbfda8d4c25b0be8f30e323c81aafe2c7c