Malicious PDF — malware analysis report

Static analysis result for SHA-256 8338f35ba5f4c80c…

MALICIOUS

PDF

68.0 KB Created: 2021-09-27 08:56:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 391b884ee0bd3506a9df2aae79c74ce6 SHA-1: a863469201b0ade6c2899ed6f042dd689eb64317 SHA-256: 8338f35ba5f4c80c423814195bf7a1523ccf901aa1e207fcdbbc1624bc078428
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it is a link farm pointing to compromised websites and disposable hosting. The embedded URLs, such as 'https://infrive.ru/uplcv?utm_term=unlimited+money+download', suggest a phishing or malware distribution lure. The PDF structure and embedded links are consistent with a phishing attack leveraging a malicious document as an attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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 https://infrive.ru/uplcv?utm_term=unlimited+money+download PDF link annotation
    • http://xn--80aikni6a0b.xn--p1ai/images/file/nemoduwewijalax.pdfIn PDF document text
    • http://vectorma.ru/uploads/assets/file/23772426733.pdfIn PDF document text
    • https://nhahangphongcanh.com/uploads/files/76192613523.pdfIn PDF document text
    • http://xageunion.com/userfiles/file/90180825234.pdfIn PDF document text
    • http://naoshima-habitant.com/images/blog/file/ziradupo.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/39500256017.pdfIn PDF document text
    • https://parisnordmedical.fr/docs/file/benetivukida.pdfIn PDF document text
    • https://truckforceone.com/upload/editor/file/44984565444.pdfIn PDF document text
    • https://nbcmedia.vn/ckfinder/userfiles/files/46409269626.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614685e84369b---wivuvisunoxofofusobevo.pdfIn PDF document text
    • https://ilexgold.com/app/webroot/files/userfiles/files/topavudi.pdfIn PDF document text
    • https://aakritidigitals.com/userfiles/files/wonagugijosoz.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/161329a833c26d---69784949815.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/vobazin.pdfIn PDF document text
    • http://wlpp.net/images/blog/file/musenupelanasusa.pdfIn PDF document text
    • http://gtlitalia.com/userfiles/files/futobanogulubidini.pdfIn PDF document text
    • https://invision.buzyhub.com/files/selexogonunuduluk.pdfIn PDF document text
    • https://gsm.company/ckfinder/userfiles/files/20188226161.pdfIn PDF document text
    • http://bankerz.in/qpic/files/46612276031.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/livegapabisup.pdfIn PDF document text
    • http://snieznik.pl/userfiles/file/89198369199.pdfIn PDF document text
    • http://tajeer.co/userfiles/file/96845447152.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/vnt32vs0qc5krn4s6mrc92beq3/93282431039.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_off0000add5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xADD5 14760 bytes
SHA-256: d9500d8619ac6186039cb237f431f8b8619d73c92ee80e681fe4f0a33af71e0a
font_01_sfnt_off0000d32c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD32C 10348 bytes
SHA-256: d85db88d8e2351d33c16a283e6b886f6285c3cdc806b74fffdc4987880e71fab
font_02_sfnt_off0000ea86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1