Malicious PDF — malware analysis report

Static analysis result for SHA-256 58324efd7e3503b3…

MALICIOUS

PDF

80.1 KB Created: 2021-09-09 19:35:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e9ddb6b7137a9cd5cab21ccfb601c6e0 SHA-1: b83744379ee6d9f5dac0040f7e98a9b83f6555c3 SHA-256: 58324efd7e3503b3f4086a00f211a149126e21128ced75ca0009e897769d2e71
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Numerous heuristics identified it as a link farm, with many external URIs pointing to potentially compromised or disposable hosting. The presence of embedded URLs and the PDF structure suggest it is designed to redirect users to malicious websites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://krisoc.ru/uplcv?utm_term=play+games+apk+mod PDF link annotation
    • http://taiwan-casters.com/userfiles/file/81567434710.pdfIn PDF document text
    • https://tour-paris-guide.com/cite_imgs/file/541787453.pdfIn PDF document text
    • http://belean.pl/userfiles/file/zujimavube.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/94810353007.pdfIn PDF document text
    • https://limadelimon.com/images/file/dirijufitup.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613345925fb06---fobakixak.pdfIn PDF document text
    • http://highdesertrent.com/newsite/images/uploads/file/81065226648.pdfIn PDF document text
    • https://www.eos.org.eg/ckfinder/userfiles/files/27250589555.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/mutizomelufofogam.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/63684354702.pdfIn PDF document text
    • https://essaidafm.com/uploads/FCK_files/file/52748512741.pdfIn PDF document text
    • http://unsersohn.com/images/file/vagufuwer.pdfIn PDF document text
    • http://becskeicsodajo.hu/admin/fck_upload/file/55129166212.pdfIn PDF document text
    • http://jiehuist.com/userfiles/files/pofepuzebozodat.pdfIn PDF document text
    • http://abwingsde.com/uploads/files/77786022485.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16131b2bc57acb---19715565773.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/17180069479.pdfIn PDF document text
    • http://hnfhdc.com/UpLoadFile/2021090914284054969.pdfIn PDF document text
    • https://adikkedua.com/contents/files/jatojodiwatelamuv.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138a88fe8c8b---68917247505.pdfIn PDF document text
    • http://nieruchomosci-swidnica.pl/userfiles/file/buwototazomisinu.pdfIn PDF document text
    • https://777mto.com/contents/files/revebajimitivujokabu.pdfIn PDF document text
    • https://megalightgroup.lv/uploads/files/rubadeperiran.pdfIn PDF document text
    • http://lynxitservices.com/ckfinder/userfiles/files/45593094128.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_off0000d7b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B9 10548 bytes
SHA-256: 0616178bfc05c6530959a4e025296dadd65a95f98e665a2f76dd172cea220c64
font_01_sfnt_off0000efa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107B2 16884 bytes
SHA-256: 5b53664b834d006613ae508e871eb905e8e5e4028dcdb10cee6743e262f41008